an acronym used to quickly tell someone to leave you alone and go away, taken from the first letter of each word in the phrase Eat Shit And Die.

I couldn’t care less (but one must keep up appearances, right?)

Translates to "Eat Shit And Die".

e.s.a.d. stands for eat shit and die. its a good nickname someone that is really pissing you off because most people can not figure out what it means and if they do figure it out they will feel that there definition is right because they will feel like why would you call someone eat shit and die.

Acronym that means "eat shit and die"

It can an also be extended to "eat shit, and then die" ESATD

Or if you mean serious business,

"Eat shit and then die, you dumb asshole." ESATDYDA

At which point it looks like a Mexican celebration phrase in ALL CAPS.