The headword noun means a "parasite" not in the modern entomological sense, but rather someone who "dines alongside"; a meal-moocher, usually with a reputation for flattering.
[1] Similarly in other lexica.
[2] Repeated at tau 908.
[3] Likewise in other lexica; references at Photius pi304 Theodoridis. The term presumably implies slapping the table in glee at the host’s jokes. Used as a comic proper name, apparently, in Alciphron.
[4] Aristophanes, Plutus [Wealth] 175 (web address 1 below). A scholiast to the line ("And will not the needle-seller [suffer] along with Pamphilus?") identifies the needle-seller as one Aristoxenos -- ignored in LGPN ii -- and details his unsavory behavior.
[5] Prosopographical orthodoxy takes this to be the most politically prominent Pamphilos of the era, P. of Keiriadai (LGPN ii s.v. no.52; J.K. Davies, Athenian Propertied Families 365; R. Develin, Athenian Officials 216), recently in the news as one of the generals of 389/8 and a defendant in a prosecution for embezzlement.