The phrase "to see off" means to send someone or something away, usually in a formal manner. It can refer to seeing someone off at an airport, train station, bus stop, etc., as they depart on a journey or trip. The term is also used figuratively to describe saying goodbye to someone who is leaving their job, moving away, or ending a relationship. In this sense, "to see off" means to give the person a proper send-off and show them your appreciation for their contributions or friendship.