Hubba, hubba

Hubba, hubba is an American slang interjection or exclamation that expresses surprise, admiration, or approval, especially when directed at a member of the opposite sex. It is first attested from the 1940s and was a favourite expression used by American GI's during WWII. It may have been around before this in vernacular speech, but there are no credible citations or attestations in print or broadcast media for this. The origin is obscure and remains unproven despite theories that it derives from Chinese, the word hubbub, or the military words hup, hup used by drill sergeants in the army.