grime (n.) Look up grime at Dictionary.com
1580s, of uncertain origin, probably alteration of Middle English grim "dirt, filth" (early 14c.), from Middle Low German greme "dirt" or another Low German source, from Proto-Germanic *grim- "to smear" (source also of Flemish grijm, Middle Dutch grime "soot, mask"), from PIE root *ghrei- "to rub" (see chrism). The verb was Middle English grymen (mid-15c.) but largely was replaced early 16c. by begrime.