Word Definition - 人不可貌相

rén bù kě mào xiàng you can't judge a person by appearance (idiom); you can't judge a book by its cover; often in combination 人不可貌相,海水不可斗量[ren2 bu4 ke3 mao4 xiang4 , hai3 shui3 bu4 ke3 dou3 liang2]