| adust | adj. | burnt up, scorched | ||
| advent | n. | arrival, coming into being; (usu. Advent) ecclesiastical season during the four Sundays before the Nativity; (also usu. Advent) the coming of Christ into the world, thus sometimes the Second Coming | ||
| adventitious | adj. | accidental, supervenient, extrinsic | ||
| adversion | n. | attention | obsolete | |
| advowson | n. | right to nominate person to fill an vacant church benefice | British | |
| aelurophile | n. | (also ailurophile) cat lover | ||
| Aeolian harp | n. | stringed musical instrument constructed so that its sounds are produced by the wind passing over and through the strings | ||
| aerobate | v. | to perform dramatic maneuvers with aircraft | ||
| aerodyne | n. | heavier-than-air aircraft which fly through use of aerodynamic forces | ||
| aerolite | n. | rocky meteorite (as opposed to one composed of iron and nickel) | ||
| afferent | adj. | leading inward or conducting towards, as of nerves or other physiological pathways to organs | biology | |
| afflatus | n. | divine inspiration, inner creative impulse | ||
| againward | adv. | once more; back again | ||
| agal | n. | cord around keffiyeh holding it in place | ||
| agenesis | n. | failed or anomalous development of body or part; sterility | ||
| agistment | n. | act of allowing the livestock of others to graze on one’s land for a specified rate; type of tax for specified purpose | ||
| agita | n. | irritation, upset, anxiety; indigestion | ||
| agnomen | n. | fourth name given to some Roman citizens in addition to the praenomen, nomen, cognomen; nickname | ||
| agon | n. | a conflict, especially between a protagonist and an antagonist in a work of literature | ||
| agrestal | adj. | of or related to plants wildly growing in cultivated fields | ||
| aguishly | adv. | in the manner of a sufferer from ague; shiveringly, quiveringly | ||
| agynary | adj. | not having female organs | botany | |
| aibohphobia | n. | fear of palindromes | ||
| aigrette | n. | egret crest feather or feathers used as headwear decoration, or similar decorations formed of jewels | ||
| ailurophile | n. | lover of cats, cat fancier | ||
| al fresco | adj. | outside, in dining | ||
| albescent | adj. | becoming white; whitish | ||
| ale-bush | n. | tavern sign | ||
| aleatory | adj. | unpredictable, random, depending upon the throw of a die | ||
| aleconner | n. | inspector of ale | ||
| alethic | adj. | way a language speaks of truth | ||
| alexithymia | n. | inability or deficiency in experiencing or grasping emotions | ||
| algesia | n. | sensitivity to pain | ||
| algolagnia | n. | sadomasochism, sexual gratification from either inflicting or enduring pain | ||
| alicorn | n. | horn of a unicorn, esp. as medicinal ingredient | ||
| alidade | n. | sighting instrument used for measuring angles (both horizontal and vertical) from a fixed point | ||
| alinea | n. | another name for the pilcrow, a typographical mark used to designate a paragraph (“¶”) | ||
| aliquot | n. | exact proper divisor (that is, a number which can divide a larger number without leaving any remainder) | ||
| all my eye and Betty Martin | n. | balderdash, nonsense | idiom | |
| allelomimetic | adj. | of or related to actions likely to be copied by nearby members of a social animal group | ||
| allocution | n. | formal or hortatory speech; pontifical address to secret consistory | ||
| allodial | adj. | of property held absolutely without rights accruing to a feudal superior | ||
| allopathy | n. | treatment of disease by producing effects opposite to the disease’s symptoms; derogatory term for traditional medicine | ||
| allotropic | adj. | existing (of an element) in multiple physical forms | ||
| almoner | n. | distributor of alms; hospital social worker | ||
| alula | n. | small bunch of feathers on the forward wing of a bird, controlled similarly to a ‘thumb’, used at slow flight speeds or when landing | ||
| aluminium | n. | aluminum | British | |
| amain | adv. | at full force, violently; at full speed | ||
| amanuensis | n. | one who writes from dictation, copyist, secretary | ||
| amaurosis | n. | total or partial loss of sight, usu. without external changes to the optic orb |