From Longman Dictionary of Contemporary Englishlookalikelook‧a‧like, look-alike /ˈlʊkəlaɪk/ noun [countable] informalLIKE/SIMILAR someone who looks very similar to someone who is famous a Madonna lookalike
Examples from the Corpus
lookalike• Fifteen years ago the Renault 12 lookalike needed just over six litres to cover 60 miles the current model drinks seven.• Both are Hollywood-style productions, one a soppy Western, the other a slapstick item featuring a Chaplin lookalike.• Coming towards him, big smile freezing fast, was this Julie Christie lookalike in Fringed Suede.• Mao lookalikes also dominate the cinema.• Victoria's lookalike sister Louise, 24, arrived with a male pal who was the image of Becks.• In the meantime, maybe he would offer him the girl, the lookalike.• She's one of five winners of the lookalike contest.