The act of carelessly poring your beer aggressively so it foams up past the rim and the contents of the glass are largely wasted. Dorf Foam can also be found in a beer bottle if its been agitated or consumed too quickly.

A term that has become increasingly popular with origins linked to the YouTube Drinking Community. Y.T.D.C
" After drinking that 40oz, he didn't leave any Dorf Foam in there."
by The Shmitt September 16, 2017
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