When you're jacking off to porn and when the video stops to buffer you become too impatient for the video to resume so you just cum during the buffer screen.
"Dude I was watching this Dillion Harper vid last night on my phone but I only had 4G."

"Oh no, did you buffer nut?"

"Yea. I gotta get better internet..."

"Sick dude, let's blow each other."
by ThisIsMatthewCastro June 22, 2018
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nuht buhf-fer

noun; the human tongue, used in a sexually derogatory fashion

verb; the sexual act of licking a man's testicles with exhausting vigor

See also; cunt scrubber
1. Langston needs to quit wagging his nut buffer and get back to work!

2. My girlfriend gave me a serious nut buffer. Dig deep, baby. Dig deep.
by Mr. Magnificent the Elder March 8, 2014
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