The act of wagging your penis in the same manner that a duck shakes its tail to get water off. Instead of wagging to get water off, you wag until you ejaculate.
'Chris did the duck shake all over his girlfriend, after she asked him to clean the room.'
The act of taking one leg and moving it back and forth while going forward. The king of rock n' roll, Chuck Berry, perfected this move and since then millions have copied this move but only one person other than Chuck can perform it, Angus Young.
Dude, you suck at the duck walk. Stop trying to be like Chuck or Angus.