wont

apt, inclined, liable, likely, prone

hardened, inured

experienced, practiced (or practised), seasoned, veteran

addicted, hooked

addiction

disposition

bent, inclination, proclivity, set, tendency, tenor, turn

bag, convention, form, mode, style

usage, use

deportment, manners, mores

drill, groove, jog trot, regime (also régime), regimen, rote, routine, rut

affectation, airs, pose

attribute, characteristic, mark, trait

eccentricity, kink, oddity, peculiarity, quirk, singularity, tic