Air, bearing, carriage, demeanor.
Akin, alike, identical.
Alert, on the alert, sleepless, wary, watchful.
Allay, appease, calm, pacify.
Alliance, coalition, compact, federation, union, fusion.
Allude, hint, imply, insinuate, intimate, suggest.
Allure, attract, cajole, coax, inveigle, lure.
Amateur, connoisseur, novice, tyro.
Amend, better, mend, reform, repair.
Amplify, develop, expand, extend, unfold, widen.