Phonetically pronounced "Meeeeeee-heeeeeeeellllll-shhhh" and in rapid succession. This is the sound that Eastern European males make when ejaculating upon a female.
Petr roared "Milsch" after his money shot in Euro-Block Butt Party 7.

Or when used as a verb, "Steve really milsched that bitch last night"
by Cic and Conk January 25, 2008
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