Definitions by Mr. Led Zeppelin

Methane Mouthwash 

When you drop your drawers and bare-ass fart into your sleeping friend's open mouth as they are breathing in, causing them to jump awake and spit.

Dude, John is passed out with his mouth wide open. You should go and give him a methane mouthwash and see how fast it makes him stop snoring!

Methane Mouthwash by Mr. Led Zeppelin March 21, 2020

Deathane 

When the methane gas expelled from your rectum smells so bad, that it actually has the potential to bring death upon another person!

"My God, Harry! If you leak one more of your Deathane farts, I am gonna die of either suffocation or choking on my own vomit!"

Deathane by Mr. Led Zeppelin March 17, 2020