falling or tripping without grace onto a hard surface, usually resulting in "battle wounds"
I didn't mean to kerflop onto that curb, it just happened; now I've got a nasty gash to prove it.
by CT921 April 14, 2008
The sound a mans testicales make when he sits down a toilet seat lid, and his testicals hit the water inside of the toilet.
I'll be right out! *Ker flop*.
by Robert Kahn May 18, 2005