Geronimo!

Geronimo!

An exclamation of excitement, typically used when one does something daring, especially jumping from a height. Jake peered out the open door of the airplane and yelled "Geronimo!" as he leapt out.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

Geronimo!

(dʒəˈrɑnəmo)
exclam. Here I go! (Originally said by parachutists leaving a plane. From Spanish for Jerome.) There’s my cue. Geronimo!
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
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References in periodicals archive ?
"Words aren't enough to describe how proud I am right now, how proud I am of The Sarah Geronimo!! She really is the best representative of the Philippines in events like this!
Of course, the night wouldn't be complete without the band singing their number one hit "Geronimo." Everyone jumped and danced as they sang along to the song's catchphrase "Say Geronimo!"
While leading a charge against Mexicans they began to shout 'Geronimo!' seeking help from their patron saint, Jerome, or Geronimo in Spanish.