Perhaps a reduplicated form of pee, but compare French pipi, German Pipi, Italian pipì, Latin pipinna, Romanian pipi, Spanish pipí, and Turkish pipi.
- (colloquial, usually childish) Urine.
- (colloquial, usually childish) The penis.
2004 Eminem "Ass Like That" (song) "I ain't never seen an ass like that/ The way you move it, you make my pee-pee go da-doing, doing, doing".
pee-pee (third-person singular simple present pee-pees, present participle pee-peeing, simple past and past participle pee-peed)
- (hypocoristic, slang) To urinate.