Residuface occurs when someone has an amusing conversation in one room, then leaves but they still have a stupid smile or grin on their face while entering the next room, which often looks moronic to onlookers
"Darn, I was just in the lunchroom joking around with my secretary when I walked out and my boss looked at me and I had a dumb looking Residuface"

e.g. "Residual Face"
by Quandushi December 17, 2009
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