ratfink

n (US sl derog 俚, 贬) 1 unpleasant person 讨厌的家伙. 2 informer 告密者.

rascally, rase, rash, rasher, rashly, rashness, rasp, raspberry, raspy, Rastafarian, rat, rat-a-tat-tat, rat-tat, ratatat, ratbag, ratchet, rate, rate-capping, rateable, ratepayer, rather, rather than, rather too, ratification, ratify, rating, ratio, ratiocination, ration, rational, rationale, rationalism, rationalist, rationalistic, rationality, rationalization, rationalization, rationalisation, rationalize, rationalize, rationalise, rationally,