A male, usually of the small, gingery, freckled variety, who uses his innocent appearance and mastery of the English languages to woo females, despite the fact that he resembles nothing more than an undernourished red squirrel that is too stupid to come in out of the rain. When his duplicitous nature is eventually uncovered, he lashes out with ineffective character assassinations. A Mack is never a serious threat, because, despite his advanced vocabulary, he still has a weak grasp on the difference between "your" and "you're".
It's a Mack! Quick, beat him over the head with Strunk and White's Elements of Style before he seduces that innocent girl!