To forcefully insert ones entire flat hand into the vagina (fingers first) in a one swift, fluid motion.

A sexual manoeuvre only for seasoned veterans and not for the feint hearted.
Clitoral stimulation can then be applied with rotations of the thumb.
Carl gave Sophie a fishslice. She then gushed.
by the diddler March 14, 2015
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A spatula-like cooking implement with holes in, used for flipping fish and frying other things.
Bob: 'My spatula just won't turn that fish!'
Bill: 'Use a fishslice!'
by BlueFladoo July 24, 2006
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