FAREWELL
bid adieu to someone or something and bid someone or something adieu
to say good-bye to someone or something. (This adieu is French for good-bye and should not be confused with ado.)Now it's time to bid adieu to all of you gathered here.He silently bid adieu to his favorite hat as the wind carried it down the street.
so long
good-bye. (Informal.)So long, see you later.As John got out of the car, he said, "Thanks for the ride. So long."
Take it easy
Good-bye and take care of yourself. (Informal.)Bye, Tom. Take it easy.Take it easy. I'll see you later.