1. given to the overuse of long words - sesquipedalian orators - this sesquipedalian way of saying one has no money • Similar to: pretentious • Derivationally related forms: sesquipedality 2.(of words) long and ponderous; having many syllables - sesquipedalian technical terms • Syn: polysyllabic • Similar to: long • Derivationally related forms: sesquipedality, polysyllable (for: polysyllabic)