adj. pertaining to oddly shaped and easily noticeable birthmarks located on one's face or head; usually pink or brown in color.
by Laurcass April 20, 2006
The term 'dirty Gorbachev' can only be achieved when your sexual partner has an exceptionally large forehead. This act is described as leaving a shit mark on your partner's forehead by taking your cock out of their ass and slapping it across their forehead without wiping it off first. The result is that is that the dick leaves a mark similar to that of the prominent birthmark of Mikhail Gorbachev.
To clearly demonstrate Scott's mastery of sexual deviancy, he would regularly plant a dirty Gorbachev on his girlfriends forehead after anal.
by fastaire33 December 19, 2018