About the etymology of the word “bombshell” to describe a beautiful woman: A “bombshell” can be any shattering or devastating act or event. A “blonde bombshell” wasn’t simply a good-looking gal, but one whose vitality or physique were downright startling. It’s not entirely unrelated to the war, however: this meaning of “bombshell” came into use only in 1942. (Source: Oxford English Dictionary.) An alternative theory suggests that the origin is in 1933, when Jean Harlow released a movie named “Bombshell”, and one of the tags was “Lovely, luscious, exotic Jean Harlow as the Blonde Bombshell of filmdom.” WWI was done in 1918.