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1.
to alernatly smush and/or ruffle another's hair with hands, usually in a side to side motion.

this word comes from combining the two words "smush" and "ruffle" while slurring the beginning a bit.
"Oh, that guy is so fuzzy. I just want to go up to him, schmuffle his hair, and say, "Will you marry me?"
by J gleason April 11, 2006