The act of performing fellacio to the point of gagging, not once, not twice, but repeatedly. The gagging won't stop you from sucking his cock.
"My girl was on a gag-a-thon last night!"

"Dude, right on!"
"Word. I kept thinking she'd stop but that gagging didn't stop her from going down."
"Awwwww shit."
by DonkeyDo January 27, 2011
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