turning one's coat

Verb

turn one's coat (third-person singular simple present turns one's coat, present participle turning one's coat, simple past and past participle turned one's coat)

1. (idiomatic) To turn against a previous affiliation or allegiance.
   • To meet the exigence of the moment, a considerable army was raised under General Baillie, a Presbyterian officer of skill and fidelity, with whom was joined in command the celebrated Sir John Urrie, a soldier of fortune like Dalgetty, who had already changed sides twice during the Civil War, and...1819, Sir Walter Scott, A Legend of Montrose
2. Used other than figuratively or idiomatically: see turn, coat.

   Synonyms:

   change sides, defect