turncoat

Noun

Synonyms: deserter apostate renegade recreant ratter

WordNet 3.0

Noun (1)

a disloyal person who betrays or deserts his cause or religion or political party or friend etc.Synonyms: deserter apostate renegade recreant ratter

Webster's Dictionary (GCIDE)

Turncoat \Turn"coat`\ (t[^u]rn"k[=o]t`), n. One who forsakes his party or his principles; a renegade; an apostate; a defector to the enemy. [1913 Webster]

He is a turncoat, he was not true to his profession. --Bunyan. [1913 Webster]