back-hander

/B AE1 K AE0 N D ER0/
noun
  1. 1

    A glass of wine given out of turn, the bottle having been handed backwards.

  2. 2

    A blow with the back of the hand.

  3. 3

    A bribe, a secret payment.

  4. 4

    (racquet sports) A shot played backhand, a backhand stroke.

  5. 5

    A surfer who approaches a swell with the wave behind them ("on their backhand") rather than facing the wave ("on their forehand").

Source: https://en.wiktionary.org/wiki/back-hander, https://en.wiktionary.org/wiki/backhander