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aberration - (noun) an optical phenomenon resulting from the failure of a lens or mirror to produce a good image; a disorder in one's mental state; a state or condition markedly different from the norm
abeyance - (noun) temporary cessation or suspension
abortive - (adj.) failing to accomplish an intended result
acerbity - (noun) a sharp sour taste; a sharp bitterness; a rough and bitter manner
acumen - (noun) a tapering point; shrewdness shown by keen insight
accolade - (noun) a tangible symbol signifying approval or distinction
Ad hoc- (adverb) for the special purpose or end presently under consideration
adjudicate - (verb) bring to an end; settle conclusively; put on trial or hear a case and sit as the judge at the trial of
adumbrate - (verb) give to understand; describe roughly or briefly or give the main points or summary of
affinity - (noun) a natural attraction or feeling of kinship; inherent resemblance between persons or things; the force attracting atoms to each other and binding them together in a molecule;(immunology) the attraction between an antigen and an antibody; a close connection marked by community of interests or similarity in nature or character; (biology) state of relationship between organisms or groups of organisms resulting in resemblance in structure or structural parts; (anthropology) kinship by marriage or adoption; not a blood relationship
aficionado - (noun) a serious devotee of some particular music genre or musical performer; a fan of bull fighting
ambivalent - (adj.) uncertain or unable to decide about what course to follow
anachronism - (noun) an artifact that belongs to another time; a person who seems to be displaced in time; who belongs to another age; something located at a time when it could not have existed or occurred
apocryphal - (adj.) being of questionable authenticity; of or belonging to the Apocrypha
apogee - (noun) apoapsis in Earth orbit; the point in its orbit where a satellite is at the greatest distance from the Earth; a final climactic stage; highest or most distant point; climax
apostate - (adj.) not faithful to religion or party or cause; noun a disloyal person who betrays or deserts his cause or religion or political party or friend etc.
apotheosis - (noun) the elevation of a person (as to the status of a god); model of excellence or perfection of a kind; one having no equal
apropos - (adj.) of an appropriate or pertinent nature; adv. by the way; at an opportune time
ascetic - (adj.) practicing great self-denial; pertaining to or characteristic of an ascetic or the practice of rigorous self-discipline; noun someone who practices self denial as a spiritual discipline
attrition - (noun) the act of rubbing togeter; wearing something down by friction; a wearing down to weaken or destroy; sorrow for sin arising from fear of damnation; the wearing down of rock particles by friction due to water or wind or ice; erosion by frictionh