Words at Play : Top 10 User-Submitted Words, Vol. 7
Definition:
(verb) : to descend from a flying helicopter by sliding down a thick rope
Example:
"He and the eleven other SEALs on 'helo one,' who were wearing gloves and had on night-vision goggles, were preparing to fast-rope into bin Laden's yard." Nicholas Schmidle, The New Yorker, August 8, 2011