What is Rod Knock?
1.
The sound made during sexual intercourse, in the "doggy style" position, as the testicles of the male smack against the vagina of the female with the thrusting motion. The "rod" or "penis" is "knocking" or "pounding" the interior of the vagina.
"Damn dude I gave this trick rod knock last night when i was hittin' it from the back. I did work son!"
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