apprehend, v. [arrest], [seize]; [understand], recognize, consider believe; [anticipate], [dread], [fear].

apprehension, n. [seizure]; [arrest]; [opinion], [conception], [belief], [notion]; [understanding]; [fear], [dread], [anxiety], solicitude, [alarm].

apprehensive, a. [discerning], [apt]; [fearful], [anxious], worried.

approachable, a. accessible. Antonym: [unapproachable].

appropriate, a. [fitting], [proper], [applicable], apposite, [pertinent], [fit]. Antonyms: See inappropriate.

approval, n. approbation, [sanction], commendation, [liking], indorsement. Antonyms: See disapproval.

approve, v. [commend], [sanction], [countenance], [favor], [like].

apron, n. [pinafore], tier; [boot].

apt, a. [fit], [relevant], [appropriate], [germane], [applicable], felicitous, [pertinent], apropos; [likely], [liable]; [clever], [intelligent], [bright], [deft]. Antonyms: See inapt.

aptitude, n. proneness, propensity, [leaning], proclivity, [inclination]. Antonym: inaptitude.