1 definition by castigrl4

The tiny specs of crunchy looking balls of sweaty dirt that fall off on to the back rim of the toilet seat, from just above your ass crack. Similar to dingle berries, these crusty little dustings collect usually after wiping occurs.
"MOM, Michael left BUTT CRUSTIES on the back of the toliet seat again".
by castigrl4 January 4, 2008
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