A performer who entertains people by speaking without moving their lips, making it seem that the words come from a puppet — a doll, usually shaped like a person, that sits on their knee. That puppet is called a dummy. The classic act is a conversation between the two: the dummy is rude or silly, the ventriloquist plays the calm one, and the joke is that the performer is really saying both sides. You see ventriloquists on television talent shows, at children's parties, and in old variety theatre; it is a slightly old-fashioned kind of act that keeps coming back. The word is also used loosely: if one person is really controlling what another person says in public, someone might call the speaker a puppet and the one behind them a ventriloquist. Note the adjective ventriloquial exists but is rare — people just say 'a ventriloquist act' or 'a ventriloquist's dummy'.