junket (n.)

late 14c., jonket, "basket in which fish are caught or carried," from Medieval Latin iuncata "rush basket," perhaps from Latin iuncus "rush" (see jonquil). The English word shifted meaning by 1520s to "feast, banquet," probably via the notion of a picnic basket; this led to extended sense of "pleasure trip" (1814), and then to "tour by government official at public expense for no discernible public benefit" (by 1886, American English).

Compare Italian cognate giuncata "cream cheese-like dish" (so called because originally made or served on a bed of rushes); Middle English jonket also had this sense, which survived longer in dialects. Johnson (1755) also records a verb junket "to feast secretly; to make entertainments by stealth."