An incredibly overused term thats short for "Greatest Of All Time", mostly used by people below 20 (at the time of writing) that don't really have the experience to make such a claim. A funny meme or good joke or nice sandwich is enough to get the "Greatest Of All Time" label because most people using this term are young and simply unaware of actual "GOAT" things.
Some people even go the extra step of using the wrong grammar, as if they are talking about goats the animal, because why not (see second example)
Some people even go the extra step of using the wrong grammar, as if they are talking about goats the animal, because why not (see second example)
by S_Banana August 21, 2023
Get the goatmug. 
When a guy is having explosive diarrhea while their partner is giving him a blowjob simultaneously. The feces is so explosive that it splashes out of the toilet bowl and covers the partners chin, resembling a goatee.
by Gary Giveittoya October 16, 2020
Get the Stinky Goatmug. by supyoheyhi January 10, 2021
Get the goat of fragmug. 
Bend her over spread cheeks and lick while making billy goat noises then headbutt the butthole and finish then faint
by Smokeydd July 7, 2023
Get the Billy goatmug. 