80 synonyms for companion such as guide, ally, aide, accessory, abc, and bible. Companion is a noun, and its antonyms are enemy and stranger.
Ally, amigo, associate, buddy, china, chum, co-worker, colleague, compadre, compatriot, compeer, comrade, confederate, confidant, confidante, confrère, consociate, consort, crony, cully, escort, friend, gabba, homeboy, homegirl, intimate, marra, marrer, marrow, mate, mucker, offsider, oppo, paisan, pal, partner, sidekick, spar, and workmate.
Aide, assistant, attendant, carer, chaperone, duenna, equerry, helper, lady in waiting, minder, personal assistant, protector, protectress, sidekick, squire, and valet.
Accessory, accompaniment, addition, adjunct, appendage, auxiliary, complement, counterpart, fellow, match, mate, other half, supplement, and twin.
ABC, bible, enchiridion, guide, handbook, instruction book, manual, primer, reference book, and vade mecum.