companion

1 a person frequently seen in the company of another the reckless companions of one's youth Synonyms cohort, associate, compatriot, compeer, comrade, crony, fellow, hobnobber, mate, running mateRelated Words colleague, coworker, equal, peer, workmate; accomplice, affiliate, ally, collaborator, confederate, half, partner; buddy, chum, confidant, familiar, friend, hearty, intimate, pal; countryman; classmate, housemate, messmate, playfellow, playmate, roommate, schoolmate, shipmate, teammate; attendant, escort; hanger-on, leech, parasite

2 one that accompanies another for protection, guidance, or as a courtesy a dapper gentleman who's a frequent companion of widowed dowagers at society galas Synonyms attendant, escort, guard, guideRelated Words chaperone (or chaperon), squire; shadow, sidekick; conductor, leader, pilot; convoy, courier, honor guard, outrider

3 either of a pair matched in one or more qualities a sketch that is a companion to the original drawing Synonyms mate, fellow, half, match, twinRelated Words coordinate; coequal, counterpart, equal, equivalent, like, parallel, peer, rival; carbon copy, double, duplicate, facsimile, identical twin, likeness, mirror image, replica, ringer; analogue (or analog), similarityNear Antonyms antipode, antithesis, contrary, converse, opposite, reverse

4 something that is found along with something else the report and its companion recommendations for action Synonyms attendant, accompaniment, concomitant, corollary, incident, obbligatoRelated Words accessory (also accessary), adjunct, appendage; complement, supplement; counterpart, fellow, mate; consequence, follow-up; fixings, trimmings