Meaning

noun a decoy who acts as an enthusiastic customer in order to stimulate the participation of others

verb act as a shill

originUnknown; attested as verb 1914, as noun 1916. Perhaps an abbreviation of shillaber, attested 1913. The word entered English via carny, originally denoting a carnival worker who pretends to be a member of the audience in an attempt to elicit interest in an attraction. Speculatively an extended form of German Schieber (“black marketeer, profiteer”) via *shi-la-ber. There are some suggestions that…

Etymology from Wiktionary, CC BY-SA 3.0