payment vs payoff

Wanna be clear about the definitions and uses of “payment” and “payoff” in the context of Derivatives.

  1. It seems that “payoff” usually refers to the net gain/loss from a derivative transaction and “payoff” comes with cash settlement. While “payment” usually comes with the physical settlement. Please correct me if I was wrong.
  2. Is there any situation in which “payment” and “payoff” are interchangeable?