“bimbo” has an interesting history:

The word bimbo derives from the Italian bimbo, a masculine-gender term that means “little or baby boy” or “young (male) child” (the feminine form of the Italian word is bimba). Use of this term began in the United States as early as 1919, and was a slang word used to describe an unintelligent or brutish man.

It was not until the 1920s that the term bimbo began to be associated with women in popular culture. In 1920, Frank Crumit, Billy Jones, and Aileen Stanley all recorded versions of “My Little Bimbo Down on the Bamboo Isle”, with words by Grant Clarke and music by Walter Donaldson. The song uses the term “bimbo” to describe an island girl of questionable virtue. The 1929 silent film Desert Nights uses it to describe a wealthy female crook, and in The Broadway Melody, an angry Bessie Love calls a chorus girl a bimbo. The first use of its female meaning cited in the Oxford English Dictionary is dated 1929, from the scholarly journal American Speech, where the definition was given simply as “a woman”.

In the 1940s, bimbo was still being used to refer to both men and women, as in, for example the comic novel Full Moon by P. G. Wodehouse who wrote of “bimbos who went about the place making passes at innocent girls after discarding their wives like old tubes of toothpaste”.

The term died out again for much of the 20th century until it became popular again in the 1980s and 1990s, with political sex scandals. As bimbo began to be used increasingly for females, exclusively male variations of the word began to surface, like mimbo and himbo, a backformation of bimbo, which refers to an unintelligent, but attractive, man.