"Who's your daddy?" is a slang expression that takes the form of a rhetorical question. Use of the phrase implies a boastful claim of physical or sexual dominance over the intended listener. Comedians suggest that the phrase is frequently spoken by men in a Freudian outburst during sexual intercourse.
The phrase itself stands out as a noteworthy lyric from the 1968 song Time of the Season by The Zombies: "What's your name? Who's your daddy? Is he rich like me?"
Widespread provocative use of the phrase began as early as the late 1980's, largely due to its frequent use in sexually suggestive skits broadcast by a popular syndicated radio shock jock known as "The Greaseman".