The term 'send packing' is an idiom that means to force someone to leave or be removed from a place. This CAN be done in a variety of ways, as evidenced by the crossword solutions: DISCHARGE (9 letters), OUST (4 letters), BANISH (6 letters), EXPEL (5 letters), EJECT (5 letters), FIRE (4 letters), CAN (3 letters), SHOO (4 letters), EVICT (5 letters), AXE (3 letters), ROUT (4 letters), DISMISS (7 letters), SHIP (4 letters), and letgo (5 letters). Each of these words implies a different level of severity, but all are used to describe the same action of forcing someone to leave.