"Oom-Pah-Pah" is a lively and somewhat risqué song from Lionel Bart's musical Oliver!, sung by Nancy and the crowd at the "Three Cripples" tavern. The word "oom-pah-pah" is seemingly used euphemistically to refer to both intoxication and fornication; however, as the song points out, the word's meaning is only as dirty as the listener interprets it. Although not an original music hall song, it recalls that genre well and, in terms of both its tempo and suggestiveness, shares characteristics with such late 19th century songs as "Ta-ra-ra Boom-de-ay".
In the show the song is not even integrated into the plot; it is merely "plunked into" the beginning of Act II of the musical, after which the actual storyline resumes. In the film Oliver! (1968), it is moved to very late in the film and given a dramatic purpose; Nancy begins the song and encourages the crowd to sing and dance it with her to distract Sikes and Fagin from her attempt to help Oliver escape from Sikes' clutches, only for Bullseye to warn him.