backwhipping 

Whenever a guy is having sex with a woman from behind while she's on a heavy flow for her period, and takes his dick out and whips her on the back with it, leaving long red streaks across her back, much like when a member of a religious organization flogs themselves as a form of self punishment.

"Andrew was fucking Deanna hard from behind, and her period was really going strong, so he pulled his dick out and gave her the backwhipping of a lifetime".

backwhipping by Evil Billionaire June 16, 2011

backflipping 

adj. really, extremely. Stronger version of flippin.

Wow, your beard is backflipping amazing!
You're backflipping right it is!

backflipping by The Awesome Armchair July 24, 2008

backlipping 

back lipping
noun
a word formed by omitting a southern twang out of ones mouth slowly part of a back woods country slang which it is derived.
to speak out of ones ass

to show disrespect while dipping and chewing hay

Boy dont ye" be backlipping me.

Dont make me kick you out da trailer for backlipping me gurl.

backlipping by Quintondum Quin Alexander III December 3, 2013