[1] : WordNet (r) 2.0

sidekick
     n : a close friend who accompanies his buddies in their
         activities syn: buddy, brother, chum, crony, pal
see also:
buddy brother chum crony pal 

[2] : Moby Thesaurus II by Grady Ward, 1.0

68 moby thesaurus words for "sidekick":
   ace, amigo, associate, bedfellow, bedmate, birthmate, bosom buddy,
   buddy, bunkie, bunkmate, butty, camarade, chamberfellow, chum,
   classmate, clubmate, colleague, comate, companion, company,
   compeer, comrade, confrere, consociate, consort, copartner,
   copemate, copesmate, couchmate, cradlemate, crony, cupmate, fellow,
   fellow student, general partner, girl friend, gossip, jailmate,
   mate, messmate, old crony, pal, pard, pardner, partner, pewmate,
   playfellow, playmate, roommate, schoolfellow, schoolmate,
   secret partner, shelfmate, shipmate, shopmate, side partner,
   sidekicker, silent partner, sleeping partner, special partner,
   tablemate, teammate, tentmate, watchmate, waymate, workfellow,
   yokefellow, yokemate

Sidekick >> S Words
Sidekick, definition of term: Sidekick
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