It can mean abosultly anything you want it to. A term first used for a nick name of a boy but now used as a group friend slang term of "screw you" "Whatever" "Dumb ass" It is a word used to establish our creative minds and have the simple minds around us hearing in our conversation have no clue what we are saying even if we are insulting each other.
" KAPOOOOOSH!"
"UH God kapoosh to u 2"

Friend 1runs into wall
friend 2 :*Sigh* "Kapoosh"
by Meg March 29, 2005
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