R.I.P. is the abbreviated form of Latin phrase requierscat in pace which means rest in peace. Now anyone who has ever let her rip, will vouch for the fact that doing so is the farthest thing from being quiet, sedate, calm and peaceful.
In 1798 the phrase among mariners meant to move with slashing force as their ships cut through the ocean waves. This is due in large part to the fact that in 1775, mariners referred to rough water as a rip.
The phrase “let her rip” is an American colloquialism that can be traced back to 1853. The phrase is found in the 1859 edition of the Bartlett’s American Dictionary, 2nd Edition, and the phrase is described as a common slang expression that is a derivation of the British phrase “Let everything rip.”
Historically Speaking 