To unexpectedly hump one's face vigorously whilst perched atop their shoulders. The maneuver must be initiated by a running jump, where the O'straddler leaps onto the recipient's shoulders before thrusting.
Hey Fonz, did you see how Briant just totally O'Straddled Tad last night??

Yeah man, that was like, intense. He has wicked bad whip lash.
by Feral Tad June 26, 2010
Get the O'straddle mug.