look up any word, like blumpkin:
 
1.
It means poop.
The reason it's called that is because it's the sound that poop makes when it lands in the water.
(Definition from maze runner)
"You look like a pile of klunk!"
by Cold Mafia August 01, 2014
 
2.
when something/someone is sub par or doesnt meet expectations or breaks down. Also can be used to describe a feeling or state of mind.
"hey dude, your car is pretty klunks"
"hey im not feeling too well today....i feel klunks"
by meepmeep111 December 07, 2011
 
3.
The sound made by a metaphorical lead balloon as it lands on the ground symbolising the way in which an unfunny joke has gone down.
Knock Knock
Who's There
Doctor
Doctor Who
Exactly
Klunk !
by Bunter October 13, 2004