1 definition by MikeAllen

Substance that results from the mixing of semen and vaginal fluids that rolls down the nut sack and grundle after unprotected sex. Once mixed, if left unattended, a sticky residue will result on the nut sack and grundle with a profound citrus like smell.
Fuck man, wash up after gettin some I can smell your duck butter from over here.
by MikeAllen September 1, 2004
Get the duck butter mug.