smutch(v = verb.contact) blur, smear, smudge - make a smudge on; soil by smudging;
is one way to rub
Sample sentences: The children smutch the paper with grease ; The children smutch grease onto the paper

   A stain; a dirty spot. B. Jonson. [1913 Webster]

   To blacken with smoke, soot, or coal. B. Jonson. [1913 Webster]

VB  be unclean, become unclean, rot, putrefy, ferment, fester, rankle, reek, stink, mold, molder, go bad, render unclean, dirt, dirty, daub, blot, blur, smudge, smutch, soil, smoke, tarnish, slaver, spot, smear, smirch, begrease, dabble, drabble, draggle, daggle, spatter, slubber, besmear, bemire, beslime, begrime, befoul, splash, stain, distain, maculate, sully, pollute, defile, debase, contaminate, taint, leaven, corrupt, cover with dust, drabble in the mud, roil, wallow in the mire, slobber, slabber.

VB  be black, render black, blacken, infuscate, denigrate, blot, blotch, smutch, smirch, darken, black, sable, swarthy, somber, dark, inky, ebony, ebon, atramentous, jetty, coal-black, jet-black, fuliginous, pitchy, sooty, swart, dusky, dingy, murky, Ethiopic, low-toned, low in tone, of the deepest dye, black as jet, black as my hat, black as a shoe, black as a tinker's pot, black as November, black as thunder, black as midnight, nocturnal, nigrescent, gray, obscure.