Horse's ass American vulgar slang
Used to refer to someone who is stupid or incompetent
I felt like a horse’s ass when nobody got my joke.
Don't be such a horse's ass!
He thinks he is being cool, but actually he is just acting like a horse’s ass.
To have no money
Used to describe someone who is naive, gullible, inexperienced, easily fooled, ignorant, unsophisticated, etc.
To say, or believe something or someone that seems completely crazy, delusional, or stupid
A person who is low-witted or stupid
To be extremely stupid; not to be alert
The slang dates form the early 19th century.
To stop acting or living in a manner that is not realistic due to having experienced a very exciting time
Soon, she brought him back to earth.