Bimbo is a rude word for a young woman the speaker treats as attractive but empty-headed. It is an insult, not a fact and not a job: the speaker is putting her down, often with a sexual flavour — pretty, maybe fashionable, not taken seriously. You will hear it in films, gossip, and angry talk. It is informal and unkind. Do not use it about a real person if you want to be decent. Though actually, that is not how it began. English took it from Italian bimbo, a word for a little child, a baby boy, a variant of bambino. Around 1919, on the Italian-American stage, it meant a stupid, unimportant man. By 1920 it had slid onto women: attractive, and treated as foolish. A writer at the entertainment magazine Variety, Jack Conway, helped make it famous in the 1920s — he also spread baloney for 'nonsense' and palooka for a big stupid man. The word quietened, then came back hard in 1980s US news about politicians and sex scandals, where the woman was painted as pretty and not bright. Today it almost always targets women. A later jokey word, himbo, is used for an attractive but not-clever man, and that one is often more teasing than cruel. Some people now play with bimbo online in a knowing way, but in ordinary life it still lands as a slap.