1.verbTo incapacitate; especially by inducing disorientation or unconsciousness.
"Bill tried to stun the snake by striking it on the head."
2.verbTo shock or surprise.
"He stood there stunned, looking at the beautiful, breath-taking sunrise."
3.verbTo hit the cue ball so that it slides without topspin or backspin (and with or without sidespin) and continues at a natural angle after contact with the object ball
4.adjectiveHaving an effect that stuns.
"The stunning jolt from the taser gun made the criminal stop fleeing."