1. eat shit - Verb
2. eat shit - Interjection
(slang, vulgar, of a person) To fall and land on one's face.
Synonym: faceplant
(slang, vulgar, of an object) To experience a catastrophic breakdown.
(slang, vulgar, humorous, of a person) To do something disgusting or strongly undesirable.
(slang, vulgar) To be soundly defeated.
When he started insulting people's mothers, the bouncer made him eat shit.
Used other than figuratively or idiomatically: see eat, shit.
eat shit!
(idiomatic, vulgar) An expression of discontent or aggravation to another party.
"I fucked your sister!" "Eat shit!"
eat shit (third-person singular simple present eats shit, present participle eating shit, simple past ate shit, past participle eaten shit)
(US, slang, vulgar, chiefly Miami) To do nothing of importance; to idle.
Eat shit, dude, and may the world always remember the Fear Of A Brown Kotaku. Source: Internet