alter ego

1 a person who has a strong liking for and trust in another <over the years the state's other senator became his alter ego as well as his political ally> Synonyms friend, amigo, buddy, chum, compadre, comrade, confidant, confidante, crony, familiar, intimate, mate [chiefly British], musketeer, palRelated Words acquaintance; associate, cohort, colleague, companion, fellow, hearty, hobnobber, partner, peer, sport; blood brother, brother, main man, sister; abettor (also abetter), accomplice, ally, collaborator, confederate; pen pal; benefactor, supporter, sympathizer, well-wisher; friendlyNear Antonyms adversary, antagonist, competitor, opponent, rival; archenemy, nemesisAntonyms enemy, foe

2 something or someone that strongly resembles another <the hero of the novel is clearly the author's alter ego, right down to his receding hairline and middle-aged paunch> Synonyms image, carbon, carbon copy, clone, counterpart, doppelgänger (or doppelganger), double, duplicate, duplication, facsimile, fetch, likeness, look-alike, match, mirror image, picture, replica, ringer, spit, spitting image, twinRelated Words Chinese copy; effigy, portrait, portrayal; companion, fellow, mate; equal, equivalent; analogue (or analog), parallelNear Antonyms antithesis, converse, opposite, reverse