a word of vague etymology, perhaps a convergence of two or more words, given wide application in late 19c. and settling into its main modern meaning "floozie" from early 1920s, with a revival in 1980s.
Bimbo first appears as the name of an alcoholic punch, mentioned in newspapers from New York state (1837), Boston (1842), and New Orleans (1844, but as having come from Boston). This sense quickly fades, though it occasional is on menus as late as 1895.
From 1860-1910, Bimbo as a proper name is frequent: It is the name or part of the name of several race horses, dogs, and monkeys, a circus elephant (perhaps echoing Jumbo), and a jester character in a play. It is in the title of a three-act musical farce ("Bimbo of Bombay"), and the name of a popular "knockabout clown"/actor in England and several other stage clowns. Also it appears as a genuine surname, and "The Bimbos" were a popular brother-sister comedy acrobatics team in vaudeville.
A separate bimbo seems to have entered American English c. 1900, via immigration, as an Italian word for a little child or a child's doll, evidently a contraction of bambino "baby."
By 1920 it began to be used generally of a stupid or ineffectual man, a usage Damon Runyon in 1919 traced to Philadelphia prize-fight slang. He wrote, that July, in a column printed in several newspapers, of a hotel lobby fist-fight between "Yankee Schwartz, the old Philadelphia boxer," and another man, which Schwartz wins.
"No Bimbo can lick me," he said, breathlessly, at the finish.
"What's a Bimbo?" somebody asked "Tiny" Maxwell, on the assumption that "Tiny" ought to be familiar with the Philadelphia lingo.
A bimbo," said "Tiny," "is t-t-two degrees lower than a coo-coo—cootie."
The word does turn up in Philadelphia papers' accounts of prizefights (e.g. "Fitzsimmons Is No Bimbo," Evening Public Ledger, May 25, 1920).
By 1920 the sense of "floozie" had developed (said to have been popularized by "Variety" staffer Jack Conway), perhaps boosted by "My Little Bimbo Down on Bamboo Isle," a popular 1920 song in which the singer (imploring the audience not to alert his wife) tells of "his shipwreck on a Fiji Isle and the little Bimbo he left down on that Bamboo isle." Its resurrection in this sense during 1980s U.S. political sex scandals led to derivatives including diminutive bimbette (1990) and male form himbo (1988).
early 13c., "silly, stupid, or ignorant person," from Old French fol "madman, insane person; idiot; rogue; jester," also "blacksmith's bellows," also an adjective meaning "mad, insane" (12c., Modern French fou), from Medieval Latin follus (adj.) "foolish," from Latin follis "bellows, leather bag," from PIE root *bhel- (2) "to blow, swell."
The sense evolution probably is from Vulgar Latin use of follis in a sense of "windbag, empty-headed person." Compare also Sanskrit vatula- "insane," literally "windy, inflated with wind." But some sources suggest evolution from Latin folles "puffed cheeks" (of a buffoon), a secondary sense from plural of follis. One makes the "idiot" sense original, the other the "jester" sense.
The word has in mod.Eng. a much stronger sense than it had at an earlier period; it has now an implication of insulting contempt which does not in the same degree belong to any of its synonyms, or to the derivative foolish. [OED]
Also used in Middle English for "sinner, rascal, impious person" (late 13c.). Meaning "jester, court clown" in English is attested c. 1300, though it is not always possible to tell whether the reference is to a professional entertainer counterfeiting mental weakness or an amusing lunatic, and the notion of the fool sage whose sayings are ironically wise is also in English from c. 1300. The French word probably also got into English via its borrowing in the Scandinavian languages of the vikings (Old Norse fol, Old Danish fool, fol).
There is no foole to the olde foole ["Proverbs of John Heywood," 1546]
To make a fool of (someone) "cause to appear ridiculous" is from 1620s (make fool "to deceive, make (someone) appear a fool" is from early 15c.). Feast of Fools (early 14c., from Medieval Latin festum stultorum) was the burlesque festival celebrated in some churches on New Year's Day in medieval times. Fool's gold "iron pyrite" is from 1829. Fool's paradise "illusory state of happiness based on ignorance or erroneous judgment" is from mid-15c. (foles paradyce). Fool-trap is from 1690s. Foolosopher, a useful insult, is in a 1549 translation of Erasmus. Fool's ballocks is described in OED as "an old name" for the green-winged orchid. Fool-killer "imaginary personage invested with authority to put to death anybody notoriously guilty of great folly" is from 1851, American English.
Fool killer, a great American myth imagined by editors, who feign that his or its services are greatly needed, and frequently alluded to as being "around" or "in town" when some special act of folly calls for castigation. Whether the fool-killer be an individual or an instrument cannot always be gathered from the dark phraseology in which he or it is alluded to; but the weight of authority would sanction the impersonal interpretation. [Walsh, "Handy-Book of Literary Curiosities," 1892]