Semi-melted, slushy, gray, snow that is much deeper than it appears to be. You step in it, it fills your shoes, and you spend the rest of the day pissed off with cold, wet feet.
"Son of a bitch!!! I stepped in a whole freaking puddle of mush-mush!! Now my socks and shoes are soaked...screw you Jack Frost!!!"
by LeahAnn October 20, 2007
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