What is the meaning of residual?

noun

• Something left after other parts have been taken away.
  • usage: "there was no remainder"; "he threw away the rest"; "he took what he wanted and I got the balance"
  • synonyms: remainder, balance, residue, residuum, rest
• Often plural. ( a payment that is made to a performer or writer or director of a television show or commercial that is paid for every repeat showing)
  • usage: "he could retire on his residuals"

adjective

• Relating to or indicating a remainder.
  • usage: "residual quantity"
  • synonyms: residuary