turncoat

n. 背叛者,变节者

turn on sb, turn one's back on, turn out, turn out that (to be(do)), turn out to be, turn over, turn round (also turn around), turn sb's blood cold, turn sb/sth down, turn sth inside out, turn to, turn up, turn-about, turn-around (also turn-round), turn-off, turn-on, turn-out, turn-round, turn-up, turn...upside down, turner, turning, turning-circle, turning-point, turnip, turnkey, turnover, turnpike, turnstile, turntable, turpentine, turpitude, turquoise, turret, turreted, turtle, turtle-dove, turtle-neck, turtle-necked, turves,