ka-thunk 

Onomatopoeia of a headboard repeatedly striking a wall, ostensibly due to people fucking in the bed that holds said headboard.

I couldn't sleep last night because Jared and his girlfriend in the apartment next to mine were fucking for most of the night. All I heard was "ka-thunk, ka-thunk, ka-thunk", punctuated by an occasional moan or loud request for one party to fuck the other one harder. I let the air out of that faggot's tires for that.

ka-thunk by Nigga Ass Honky August 8, 2010

ka-thunk 

think (or any form of the word "think")

i did not ka-thunk up the word ka-thunk; it was invented by someone i kno. but i ka-thunk that the word ka-thunk deserved 2 b n a dictionary of some sort.

ka-thunk by Alcatraz Psycho Ward Outpatient September 8, 2005

Kathunk 

The sound of your brain collapsing when something too confusing or too mind blowingly awesome is said to you. If your brain was a building, kathunk would be this building suddenly falling to shambles. Beware! Many never recover.

Shannon: The reason Einstein postulates that an objects length can change with its speed is due to its rotation in the 4 dimensional space time continuum. Any thoughts?

Sarah:...Kathunk.

Shannon: Hmm.

or

Sarah: Shannon! A wild goat just kicked Santi in the nads!

Shannon:Kathunk!

Sarah: I know, right?

Kathunk by Secret Agent Alpaka May 6, 2011

kathunk 

1. Noun: The sound created by human shit hitting the water in a toilet. Often as a direct result of how large the log was and how deep the bowl is.

2. Verb: The action that brests perform when a topless female is getting fucked missionary.

1. Man, I had to hang on with both hands to try and and squelch that last kathunk.

2. I felt like I was going to break that bitches nose, you see how those things were kathunking her head?

kathunk by Sumobot March 28, 2009