Apiece, individually, severally, separately.
Apparent, clear, evident, obvious, tangible, unmistakable.
Apprehend, comprehend, conceive, perceive, understand.
Arraign, charge, cite, impeach, indict, prosecute, summon.
Arrogance, haughtiness, presumption, pride, self-complacency, superciliousness, vanity.
Artist, artificer, artisan, mechanic, operative, workman.
Artless, boorish, clownish, hoidenish, rude, uncouth, unsophisticated.
Assent, agree, comply.
Assurance, effrontery, hardihood, impertinence, impudence, incivility, insolence, officiousness, rudeness.
Atom, grain, scrap, particle, shred, whit.