abdomen: Latin abdomen = the belly, the part of the trunk between thorax and the perineum, adjective - abdominal.
abducent: Latin ab = from, and ducens = led, hence, moving from, or effecting separation.
abduction: Latin ab = from, and ductum = led, hence, movement from; verb - abduct.
aberrant: Latin ab = from, and errare = to wander, hence, deviating from normal.
accessory: adjective, Latin accessum = added, hence, supplementary.
accommodation: Latin ad = to, and modus = measure, hence, adaptation of the optical power (focussing) of the eye for shorter distances.
acetabulum: Latin acetum = vinegar (cf. acetic), and abulum = small receptacle, hence, a vinegar cup, hence, the socket for the head of the femur, adjective - acetabular.
acoustic: adjective, Greek akoustikos, related to hearing.
acromion: Greek akros = summit (cf. Acropolis) and omos = shoulder, hence, the tip of the shoulder.
adduction: Latin ad = to, and ductum = led, hence, movement towards; verb - adduct.
adenoid: Greek aden = a gland, eidos = shape or form.
adhesion: Latin ad = to, and haesus = stuck, hence, stuck to, e.g., interthalamic adhesion - variable and functionally insignificant.
aditus: Latin ad = to, towards, iter = a way, hence an opening or entrance.
adrenal: Latin ad = towards, at, ren = kidney, hence situated near the kidney (see suprarenal)
adrenergic: adjective, Latin ad = at, ren = kidney, and Greek ergon = work, hence, stimuli which cause the adrenal (suprarenal) gland to produce adrenaline. Used to specify neurons or pathways which use adrenaline as a transmitter.
afferent: adjective, Latin ad = to, and ferent = carrying (cf. ferry), hence, carrying to, e.g., axons carrying information from retina to lateral geniculate nucleus are afferents to that nucleus.
agonist: Greek agonistes = rival, hence, a muscle in apparent contest with another. Used for a prime mover.
ala: Latin wing, hence a wing-like process; plural - alae.
alaeque: Latin ala = wing (ala of nose), suffix -que = and, hence levator labii superioris alaeque nasi muscles = lifter of the upper lip and ala of nose.
allocortex: Greek allos = other (than usual), and Latin cortex = bark, hence non-laminated external grey matter. It refers to paleo- or archi-cortex, as distinct from neocortex.
alveolus: Latin a basin, hence any small hollow. Plural - alveoli, adjective - alveolar.
alveus: Latin = tray. The allusion is unclear. The alveus is a layer of fibres on the free surface of the hippocampus.
ambiguus: adjective, Latin = doubtful (nucleus ambiguus).
ampulla: Latin = a two-handed flask, a local dilatation of a tube.
amygdaloid: adjective, Greek amygdala = almond, and eidos = shape or form, hence, amygdaloid body is an almond-shaped mass.
anaesthesia: Greek an = negative, and aisthesis = sensation, hence, loss of sensation; adjective - anaesthetic.
analgesia: Greek an = negative, and algesis = pain, hence insensibility to pain; adjective - analgesic.
analogous: Greek ana = up, apart, towards, and logos = word. A part with similar function through different morphology e.g., fish gills and mammalian lungs (c.f. homologous).
anastomosis: Greek ana = of each, and stoma = mouth, hence the end-to-end continuity of 2 vessels; adjective - anastomotic.
anatomy: Greek ana = up, and tome = a cutting, hence cutting up of a body (c.f. dissection).
anconeus: Greek ancon = elbow, hence the muscle attached to the (lateral surface of the) olecranon.
aneurysm: Greek angeion = blood vessel, and eurys = wide, hence a pathological dilatation of a blood vessel.
angiography: Greek angeion (v.s.) and graphe = a record, hence a picture of a blood vessel which has been injected with a dye or radiopaque material.
anhidrosis: (anhydrosis, anidrosis) Greek an = negative, and hidros = sweat, hence absence of sweating, typical of skin deprived of its sympathetic innervation.
aponeurosis: Greek apo = from, and neuron = tendon (later applied to nerve cell and its fibres), used for sheet-like tendons. Adjective - aponeurotic.
apophysis: Greek apo = from, and physis = growth, hence, a bony process - reserved for the articular process of a vertebra; adjective - apophysial.
appendage: Latin appendere = to hang on, supplement.
appendix: Latin appendere = to hang on, supplement.
apposition: Latin appositus = placed at, hence, in contact, in juxtaposition.
aqueduct: Latin aqua = water, and ductus = drawn or led off, hence a channel for conducting fluid, e.g. the cerebral aqueduct of the midbrain, which transmits fluid from the 3rd to the 4th ventricle.
arachnoid: adjective, Greek arachne = spider, and eidos = shape or form, hence like a spiders web. This middle layer of the three meninges is spread web-like over the brain when the dura has been removed.
arbor vitae: Latin arbor = tree, and vita = life, hence, resembling the tree of life. This colourful term is used to describe the pattern of cerebellar folia seen in a median section.
archaeocerebellum: Greek archi = first, hence the oldest part of the cerebellum, which is the flocculonodular lobe.
archaeopallium: Greek archi = first, and pallium = cloak, hence the cortex which developed first in vertebrates. Often synonymous with hippocampal formation.
archicerebellum: Greek archi = first, hence the oldest part of the cerebellum, which is the flocculonodular lobe.
archipallium: Greek archi = first, and pallium = cloak, hence the cortex which developed first in vertebrates. Often synonymous with hippocampal formation.
archistriatum: Greek archi = first, and Latin striatum = streaked or fluted.
astrocyte: Greek astron = star, and kytos = cell, hence a star-shaped (neuroglial) cell.
ataxia,: Greek a = negative, and taxis = order, hence inability to co-ordinate the voluntary muscles.
atlas: Greek atlao = I sustain. Atlas was a mythical god who sustained the globe on his shoulders. The 1st vertebra sustains the skull, and its upper surface bears 2 concavities which suggest Atlas' palms, not shoulders.
atresia: Greek a = negative, and tresis = a hole, hence an absence or closure of a body orifice or tubular organ
atrium: Latin = entrance hall, adjective - atrial.
atrophy: Greek a = negative, and trophe = food, hence wasting from starvation.
auditory: Latin audire = to hear, hence, pertaining to the ear.
