delivered at the moment of parting as if in flight or retreat; "paused to deliver a parting shot at the door"; "a Parthian volley of expletives from Uncle Billy"- Bret Harte
an ancient musical horn made from the horn of a ram; used in ancient times by the Israelites to sound a warning or a summons; used in synagogues today on solemn occasions
a pernicious and malign influence that is hard to get rid of; "racism is a pestilence at the heart of the nation"; "according to him, I was the canker in their midst"