The medical term refers to both sides of something

For the health care professional, it is imperative that precision is used in the way patients’ physical conditions and diseases are described. Modern medical terms and terminology provides such precision and specificity. It facilitates effective communication and correspondence between physicians across borders and from different parts of the world. In addition, medical terminology is used in colleges of medicine and other areas of the health sciences.

A system of words, medical terminology can contain a prefix, root word, a combining vowel and a suffix to create medical terms. Medical terms describe medical aspects and diseases. Specific locations on the body are indicated by prefixes. The meanings of medical terms change with different beginnings and endings. Medical terms can contain multiple root words, combining vowels etc. A physician must be very precise when dictating a term. If a letter or word is misused or inadvertently changes, the result could be unnecessary tests and appointments. In addition, an unnecessary treatment or an incorrect diagnosis could occur. The rules that specify how the multitude of roots, prefixes, and suffixes can be combined are generally based in Latin.

Morphology of medical termsMedical terms are created using root words with prefixes and suffixes that are Greek or Latin in origin. For example, “pericarditis” means “inflammation of the outer layer of the heart.” The three parts of this term are: peri – card – itis. The prefix is “peri” and means “surrounding”. The root word is “card” which means “heart”, and the suffix meaning of “itis” is “inflammation.” So, the term “pericarditis” can be translated to meaning an inflammation surrounding the heart.By changing the prefix and suffix, the medical term can be used to describe a different heart condition. For example, “bradycardia” means slow heart rate. In this case, the three parts of this term are: brady – card – ia. The new prefix is “brady” which means “slow”. The new suffix is “ia” which is translated to “a condition or state”. So, the new meaning is “slow heart rate”.Additional examples of how this medical term can change by changing the prefixes or suffixes are as follows:Prefix changes:
Suffix changes:All medical terms must have at least one root word, but can have multiple. Also, medical terms can be without prefixes or suffixes. For example, the term “sternocleidomastoid” which is means a muscle with attachments at the sternum, the clavicle, and the mastoid. This medical term’s key parts are all roots: stern(root) – o – cleid(root) – o – mastoid(root). The vowel “o” appears between the roots and serve two purposes. They link the three roots, and they make the medical term easier to pronounce. Other vowels used for these purposes are “i” and “a”.

Another example of how the vowel “o” links the different parts of a term is “electrocardiogram”. In this case, the parts are: electr – o – cardi -o -gram. Electr (electricity), o (vowel), cardi (heart), o (vowel), gram (suffix meaning record). So, the result is a medical term which means “the record of the electricity in the heart”.Additional rules:Generally, Latin prefixes go with Latin suffixes, while Greek prefixes go with Greek suffixes.Prefixes generally end in vowels or vowel sounds as in the bradycardia example above.Root words end in vowels. An example is the vowel “o” in the term “gastroenteritis”. The parts are: gastro(root) – enteritis(suffix). Gastroenteritis is an inflammation of the stomach and intestines.Suffixes often refer to procedures, conditions, or disease processes. An example of a medical term with a suffix meaning that describes a condition is pancreatitis. The parts are “pancreas” which is the root, and then “itis” which is the suffix. Pancrea refers to the pancreas. “It is” refers the condition which is inflammation. A brief history of medical termsMedical terminology originated during the Renaissance when the discipline of anatomy begun. Practicing in Italian medical schools, early anatomists and physicians used Latin to describe various parts of the anatomy. These naming conventions have remained in place to current day. One such physician was Galen (a. d. 130-200) who authored early medical texts and was responsible for many terms. Other sources of medical terminology include:Arabic- throughout the middle ages, Arabic scholars had taught medicine and originated many terms.English- medical terminology has roots in the English language which has been pre-eminent in biomedical science over the last 50 years.Biology- is a prominent source of medical terminology going back to Carl Linnaeus (1707–1778). Linnaeus was a Swedish botanist and physician who is considered the father of modern taxonomy. He developed a binomial nomenclature which is the modern system of naming organisms. Much of his work was done in Latin.

Learning medical terms:While proficiency in Latin is not required to learn medical terminology or to become a physician, it is certainly useful to grasp the nuances of the medical terms. However, more important than learning Latin, is learning common root words, prefixes, and suffixes.Following are some of the most frequently used prefixes and suffixes in medical terminology. Memorizing these will jumpstart your learning of the medical terms. This small group of prefixes and suffixes will help with the interpretation of the larger body of medical terms. You don’t need to know whether they are prefixes or suffixes and you don’t need to know Latin.

Compiled and written by Charlotte Edwards, UCL, Aug 2004 ©

Medical (especially anatomical) terms are daunting at first. They can seem almost like a different language. It is important not to panic. Don’t attempt to memorise lists of words. Terms will soon become familiar once you start using them in the dissection room. The most useful approach is to understand the derivation of key words. Often their component parts come up time and time again, within unfamiliar words. By learning the meaning of these, you can often work out what a new word means - or see where it came from.

This glossary should help transform rote learning into something far more productive. It is by no means exhaustive, but the derivations are relevant in many subject areas. Students already familiar with Latin and/or Greek will have a head start. A short glossary of Physiology and Related Sciences is also available.

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A- = prefix denoting without Agammaglobulinaemic = blood (haem) lacks gammaglobulin Apnoea = cessation of breathing

(N.B. see also ad- and an-)

Ab = away from (Latin)

Abduction = movement of limb away from the midline of the body. Abembryonic = away from or opposite the embryo

Ad = towards, beside (Latin)

Adduction = movement of limb towards the midline of the body. Adaxial = towards the main axis

N.B. often becomes a- followed by a double letter as in the following

Affect (verb) = do something to something (Contrast effect: see under E- )
Agglutination = particles sticking to each other

-aemia = suffix denoting a specified bio-chemical condition of the blood

Hyperglycaemia = excess sugar in the blood Anaemia = reduction in the amount of haemoglobin in the blood

An- = prefix denoting without, lacking

Anaerobe = an organism that is able to live and grow in the absence of free oxygen Anaesthesia = loss of feeling or sensation in a part or all of the body

(N.B. in some cases the same meaning of ‘without’ can be conveyed by the ‘A’- alone as the prefix)

Angio- = prefix denoting blood or lymph vessels

Angina pectoris = pain in the centre of the chest occurring when the demand for blood by the heart exceeds the supply of the coronary arteries Angiogenesis = the formation of new blood vessels

Ante = before (Latin)

Anterior = near or nearer to the front. Antenatal = before birth

(N.B. do not confuse with Anti- = opposite, against)

Anti- = opposite, against Antidromic = describes impulses travelling the wrong way in a nerve fibre Anticoagulant = a drug that prevents the clotting of blood

(N.B. do not confuse with Ante- = before)

-ase = suffix denoting enzyme that breaks down a substance Lactase = enzyme that breaks down lactose into glucose and galactose Dehydrogenase = enzyme that catalyses an oxidation reaction

Arthr(o)- = relating to joints [Grk]

Aural = relating to the ear (auricula = ear, Latin)

Auriscope = apparatus used to examine the eardrum and passage leading to it

(N.B. do not confuse with oral = relating to the mouth)

Bi = two

Bicuspid = having two cusps e.g. the mitral valve of the heart Biceps = a muscle with two heads

Brachi- = related to the arm

Brachial artery = artery in the arm running from the armpit to the elbow Brachialgia = pain in the arm

Brady- = prefix denoting slowness

Bradycardia = slowing of heart rate to less than 50 beats per minute Bradylalia = abnormally slow speech

Broncho- = prefix denoting bronchial tree

Bronchitis = inflammation of the bronchi Bronchospasm = narrowing of bronchi by muscular contraction in response to some stimulus

Calc- = relating to calcium (Latin)

Hypercalcaemia = high blood calcium Hypocalcaemia = low blood calcium

Cardi- = prefix denoting the heart

Cardiomegaly = enlargement of the heart Cardiac muscle = muscle of the heart wall

Cephal- = prefix denoting the head

Cephalocele = neural tube defect Cephalalgia = pain in the head

Corona = crown (Latin)

Corona capitis = crown of head
Coronal plane = divides the body into dorsal (back) and ventral (front) parts

Costa = rib (Latin)

Costal groove = groove on the undersurface of each typical rib behind which intercostal nerves and vessels run Intercostals = muscles running between the ribs

Cyst = an abnormal sac or closed cavity lined with epithelium and filed with liquid or semisolid matter

Cyst- = prefix denoting a bladder esp. the urinary bladder Cystitis = inflammation of the urinary bladder, often caused by infection Cystalgia = pain in the urinary bladder

Cyto- = prefix denoting cell or cytoplasm

-cyte = suffix denoting cell or cytoplasm Cytokinesis = division of the cytoplasm of the cell Chondrocyte = a cartilage cell

Di- = prefix denoting two (Latin)

Dipeptide = compound consisting of two amino acids joined together by a peptide bond Disaccharide =carbohydrate consisting of two linked monosaccharide units

.. beware confusion with dis-

Dia- = through, throughout

Dialysis = method of separating particles of different dimensions in a liquid mixture, using a thin semi-permeable membrane Diarrhoea = frequent bowel evacuations or the passage of abnormally soft faeces

Dis- = reversed or separated

Dislocation = separation of bones in a joint Disinfection = removal of infection

..easily confused with di- meaning two (e.g. disulphide) or dys- meaning abnormal (e.g. dysfunction)

Distal = situated away from the origin or point of attachment or from median line of the body

Dors- = prefix denoting the back (from dorsum, Latin)

Dorsal = situated close to the back of body or the posterior of an organ Dorsoventral = extending from back to front surface

Dys- = abnormal, painful

Dyspnoea = shortness of breath Dysgenesis = faulty development

E- (see also Ex-) = out of, outside, from

Evaginate = protrude outside a covering

Effect (noun) = outcome, arising from something: Drugs often have both good and bad effects.

Effect (verb) = have as an outcome: Drugs can effect cures.
Distinguish carefully from
Affect (verb) = do something to: Effective pain-killers may affect the patient's alertness.

-ectomy = cutting and removing

Lobectomy = removing a lobe of an organ Appendicectomy = removal of the appendix

Endo = within

Endogenous = arising within a tissue Endoderm = inner of the three germ layers of the early embryo

Epi = above, surrounding

Epidermis = outer parts of skin Epicardium = layer of tissue immediately surrounding the heart (part of pericardium), the outermost layer of the heart wall.

Eu = normal

Eupnoea = normal breathing Eupepsia = state of normal or good digestion

Erythr- = prefix denoting redness

Erythrocyte = red blood cell Erythema = redness, rubor – a flushing of the skin due to dilation of the blood capillaries in the dermis

Ex = out of, from (Latin)

Extension = opposite of flexion. The movement of a joint, in the sagittal plane, making the angle between bones greater. E.g. kicking a ball, extends the knee.

N.B. Often becomes just e-, sometimes followed by a double letter e.g.:

Effusion = escape of a fluid (e.g. blood) from tissue.

Exo = outside

Exogenous = something not usually found within tissue. Expiration = the act of breathing out from lungs

Extra = outside (Latin)

Extrapleural = relating to tissues of chest wall outside the parietal pleura. Extraembryonic coelom = the cavity, lined with mesoderm that surrounds the embryo from the earliest stages of development.

Fer- = carry (from fero = I carry, Latin)

Afferent = carry into e.g. an afferent blood vessel feeds a capillary network in an organ Efferent = carry from e.g. designated vessels that drain fluid from an organ Transfer = carry across

(N.B. do not confuse with ferr- = prefix relating to iron

ferritin = iron/ protein complex stored in tissue
ferrous compounds = compounds of iron where the iron is in its +2 oxidation state
ferric compounds = compounds of iron where iron is in its +3 oxidation state)

Fissure = a groove or cleft (from fissilis = split, Latin)

Oblique fissure = divides lung into lobes and runs around the lung Horizontal fissure = divides right lung into 3 lobes and extends laterally to meet the oblique fissure.

Flex- = bend (from flexus, Latin)

Flexion = movement of joint in the sagittal plane, usually making the angle between bones less e.g. bringing fist towards shoulder. Lateral flexion (usually of the spine) = bending to the side

Fossa = a depression or hollow, (literal translation = ditch, trench, Latin)

Iliac fossa = the depression in the inner surface of the ileum Fossa ovalis = depression on wall of the right atrium that separates the right atrium from the left. It represents the septum primum of the developing heart.

-genic = giving rise to (Latin)

-genous = arising from (Latin)
exogenous = something that comes from outside the body

Glomerulus (Latin) A small ball like structure as in kidney glomeruli, synaptic glomeruli

Haemo-, haem-, haemato-, -aem- (US hemo- etc.) = relating to blood

haemostasis = arrest of bleeding haematocrit = fraction of blood volume occupied by red cells

Hemi- = prefix that in medicine denotes the right or left half of the body

Hemianaesthesia = anaesthesia of one side of the body Hemicolectomy = surgical removal of about half of the colon (large intestine)

Hepat- = prefix denoting the liver

Hepatic artery = artery that supplies the liver Hepatic flexure = the bend in the colon underneath the liver where the ascending colon joins the transverse colon.

Hetero = different, varied

Heterozygous = describes an individual in whom the pairs of genes determining a particular characteristic are dissimilar Heterotopia = displacement of an organ or part of body from its normal position.

Histo- = prefix denoting tissue

Histology = study of the structure of tissues by means of staining techniques combined with light and electron microscopy Histogenesis = the formation of tissues

Homo = the same

Homogeneous, homogenous = having uniform properties Homologous = describing organs or parts that have the same basic structure and evolutionary origin, but not necessarily the same function or superficial structure.

Hydr- = prefix denoting water or a watery fluid (Latin)

Hydrocele = accumulation of watery liquid in a sac. Hydrocephalus = an abnormal increase in the amount of cerebrospinal fluid within the ventricles of the brain

Hyper = above normal

Hyperventilate = breathing more than normal Hyperglycaemia = an excess of blood glucose in the blood stream.

Hypo = below, less than normal

Hypodermic = below the skin Hypotension = condition in which the arterial blood pressure is abnormally low

In vitro = literally translated as ‘in glass’. Usually refers to a procedure carried out isolated from body and maintained in a tissue bath. (vitrum =glass, Latin)

In vivo = a procedure carried out with tissue in normal position within the body. (vivo = I live, Latin)

Inter = between (Latin) (N.B. do not confuse with intra!)

Intercellular = between cells Intercostals = muscles that occupy the spaces between the ribs

Intra = inside (Latin)

Intracellular = inside cells Intraperitoneal = an injection given into the abdominal cavity

Ipsi = same, self (Latin)

Ipsilateral = on the same side

Iso- = prefix denoting equality, uniformity and similarity

Isotonic = having the same osmolarity or (in physiology) effective osmolarity (taking account of the solute permeability of cell membranes). Isodactylism = a congenital defect in which all the fingers are the same length.

-itis = suffix denoting inflammation of an organ, tissue etc.

Arthritis = inflammation of a joint

Peritonitis = inflammation of the peritoneum

Kal- = relating to potassium (Kalium – hence symbol K, Latin)

Hypokalaemia = low blood potassium Hyperkalaemia = high blood potassium

Late = wide, far (Latin)

Lateral = in anatomy relates to the region or parts of the body that are furthest from the median plane

-logy = suffix denoting field of study

Cytology = study of cells Nephrology = study, investigation and management of the diseases of the kidney

-lysis = disruption, destruction or release

Haemolysis = destruction of red cells Anxiolytic = causing relief from anxiety

Medial = relating to or situated in the central region of an organ, tissue or the body (from medius = mid, middle, Latin)

Median plane (sagittal plane) = plane dividing the body or an organ into equal right and left halves Mediastinum = space in the thorax between the two pleural sacs that contains amongst other things the heart

Mening- = relating to the meninges (membranes covering the brain) (Greek)

Meningitis = inflammation of the meninges

Muco- = prefix denoting mucus (Latin)

Mucociliary = the process by which cilia move a thin film of mucus from the lower and upper respiratory tracts towards the digestive tract Mucosa = mucous membrane, a moist membrane that lines many tubular structures and cavities e.g. nasal cavity

My- = prefix denoting muscle

Myoblast = a cell that develops into a muscle fibre Myocardial infarction = death of a segment of heart muscle, which follows interruption of its blood supply

Natri = relating to sodium (Natrium - hence symbol Na, Latin)

Natriuretic factor = factor leading to extra sodium appearing in the urine Natriuresis = excretion of sodium in the urine

Nephro- = prefix denoting the kidneys (Greek)

(N.B see renal = relating to the kidney, Latin) Nephritis = inflammation of the kidney Nephron = the active unit of excretion in the kidney

Neuro- = prefix denoting nerves or the nervous system

Neurolemma = sheath of the axon of the nerve fibre Neurone = basic functional unit of the nervous system; a cell specialized to transmit electrical nerve impulses

Normo = normal (Latin)

Normocapnic = normal carbon dioxide levels within the blood. Normotensive = describes the state in which the arterial blood pressure is within the normal range

-oma = suffix denoting a tumour

Hepatoma = tumour of the liver Lymphoma = tumour of the lymph nodes

Oral = relating to the mouth (os, oris = mouth, Latin)

Oral cavity = the mouth Oral contraceptive = ‘the pill’ (taken via the mouth)

(N.B. do not confuse with aural = relating to the ear)

Ortho- = prefix denoting straight Orthodontics = branch of dentistry concerned with the treatment of the irregularities of the teeth. Orthopaedics = practice of the correction of deformities caused by disease or damage to the bone and joints of the skeleton

-osis = a diseased condition that involves the preceding part of the word

e.g. Tuberculosis, Nephrosis

Oste(o)- = relating to bone [Grk]

Para = alongside (Latin)

Parathyroid = gland beside the thyroid Paranasal = near the nasal cavity

Peri = surrounding or around (Latin)

Perineurium = sheath around nerve. Perinatal = around the time of birth.

-physis = growth

Hypophysis = outgrowth under the brain i.e. the pituitary gland

-plegic = suffix denoting paralysis

Diplegia = paralysis of both sides of the body, particularly the legs Hemiplegia = paralysis of one side of the body

Pneo- = prefix denoting breathing

Pneumo- = prefix denoting the presence of air or gas Pneumothorax = air in the pleural cavity Pneumocephalus = the presence of air within the skull

Pneumon- = prefix denoting the lungs

Pneumonia = inflammation of the lung caused by bacteria, in which the alveoli become filled with inflammatory cells and the lung becomes solid Pneumonectomy = surgical removal of the lung

Poly- = prefix denoting many, multiple

Polysome = a group of ribosomes linked together by messenger RNA molecules, formed during translation process of protein synthesis Polysaccharide = carbohydrate formed from many monosaccharide molecules joined in long linear and branched chains

Post = after, behind (Latin)

Posterior = near or nearer backend or tail Posteroanterior = from the back to the front

Proximal = situated close to the origin or point of attachment or close to the median line of the body (from proximus = nearest, Latin)

Quadri- = prefix denoting four (Latin) Quadriceps = a great extensor muscle of the leg, situated in the thigh and divided into four distinct portions Quadriplegia = paralysis affecting all four limbs
Renal = relates to the kidney (Latin)
(N.B. see nephro- = prefix denoting the kidney, Greek) Renal artery = either of the two arteries arising from the abdominal aorta and supplying the kidneys. Renal tubule = fine tubular part of nephron through which water and certain dissolved substances are reabsorbed back into the blood

-rrhage = denotes excessive or abnormal flow or discharge from an organ or part

haemorrhage = excessive bleeding menorrhagia = excessive menstrual flow

-rrhoea = flow or discharge from an organ or part

Diarrhoea = frequent bowel evacuations or passage of abnormally soft faeces. Rhinorrhoea = flow from the nose

Saccharo- = prefix denoting sugar

Disaccharide = carbohydrate consisting of two linked monosaccharide units Polysaccharide = carbohydrate formed from many monosaccharide molecules joined in long linear and branched chains

Sagittal = an anatomical plane that divides the body longitudinally into left and right parts, parallel to the median plane.

Stasis = constancy, cessation of movement (Latin)

Homeostasis = physiological process by which the internal systems of the body are maintained at equilibrium, despite variations in the external conditions.

-stoma = mouth

Stoma = in surgery, an artificial opening of a tube tracheostomy = an artificial opening (mouth) in the trachea colostomy = an artificial opening in the colon that has been brought to the surface of the abdomen ileostomy = an artificial opening in the colon that has been brought to the surface of the abdomen

Sub = under, beneath (Latin)

Sub-lingual = under the tongue Subcutaneous = beneath the skin

Super = above (Latin)

Superior = situated uppermost in the body related to another structure or surface Superficial = situated at or close to a surface

Supine = lying on the back (often a term used to describe lazy people) (Latin)

Supra = above (Latin)

Suprapubic region = area found above the pubic region (N.B. also known as the hypogastric region.) Suprarenal = above the kidney

Tachy- = prefix denoting fast, rapid

Tachypnoea = rapid breathing Tachycardia = rapid heart beat

-thermic = relating to temperature (Latin)

Exothermic = a reaction in which heat is given out Thermoreceptor = a sensory nerve ending that responds to hot and cold

-tomy = cutting

Lobotomy = incising a lobe of a organ Gastrotomy = a surgical incision into the stomach

Topo- = prefix denoting place, position and location

Topical = local, used for the route of administration of a drug that is applied directly to the part being treated Topography = study of the different regions of the body including how the parts relate to surrounding structures

(N.B. do not confuse with either, tropic = related to direction, or trophic = related to nutrition e.g. trophotropic = turning towards food

Toxi- = prefix denoting poisonous, toxic

Toxin = poison produced by a living organism, usually a bacterium Toxaemia = blood poisoning that is caused by toxins formed by bacteria growing in a local site of infection

Trans = across (Latin)

Transverse = In anatomy, situated at right angles to the long axis of the body Transverse plane (horizontal plane) = plane dividing organ into top and bottom halves

Tri- = prefix denoting three (Latin)

Tricuspid valve = valve in heart between right atrium and right ventricle, made up of three cusps Triceps = a muscle with three heads of origin

-trophic, -trophy = relating to nutrition (Greek)

Dystrophy = disordered nutrition Atrophy = wasting, reduction in size Hypertrophy = over-development

-tropic, -tropy, etc. = attracted to, turning towards, or affecting. (Greek)

Neurotropic virus = one targetting nerves Phototropism = orienting to light

Uni- = prefix denoting one

Unilateral = in anatomy, relating to or affecting one side of the body or one side of an organ or other part

-uresis = relating to or appearing in the urine

proteinuresis = protein in the urine

diuresis = extra urine

Vaso- = relating to a vessel, usually a blood vessel (Latin)