deadhead . deadhead {n.}, {slang} An excessively dull or boring person. You'll never get John to tell a joke — he's a deadhead. Categories: add yours {n.} {slang} Source: A Dictionary of American Idioms by A. Makkai, M.T. Boatner, J.E. Gates © 2024 To section: D Subscribe to: American IdiomsIdioms feedEnglish languageHome page and general feed Post my comment