See renegade in Webster's New World Roget's A-Z Thesaurus II
noun
A person who has defected:
apostate, defector, deserter, recreant, runagate, tergiversator, turncoat. (Informal) rat. See approach
verb
To abandon one's cause or party usually to join another:
apostatize, defect, desert3, tergiversate, turn. (Slang) rat. Idioms: change sides, turn one's coat. See approach, trust
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