Here is the list of Top Ten Idiomatic Expressions according to the "Official Top List" website (link below)
That bully is about to deliver his famous knuckle sandwich.
This is an idiom that most closely translates to the English idiom "What's done is done."
An idiom is a rendition of a combination of words that have a figurative meaning. Most idioms have no clear "inventor".
Idiom is correct.
to try new things
Since it was too cold to play outside she decided to make the most of the rest of the day by playing inside with her dolls.
what is a idiom about a cat
Andy Warhol - in 1968, he said " "In the future, everyone will be world-famous for 15 minutes."
"To be" is not an idiom - it's a verb.
An idiom misuse is to use and idiom in a wrong way that doesn't make sense.
The idiom "apple shiner" means the teacher's pet.
An idiom is a form of expression in a general group or culture. Something like 'It's raining buckets.' This doesn't mean there are literal buckets falling it just means it's raining hard. You most likely will have to define what each idiom means.