An idiom is a phrase that seems to be nonsense until you know the definition. Redonkulous is a slang word.
Silly, ridiculous, reDONKulous.
rotate, revolve, revolution, redonkulous.
Redonkulous is something that is unbelievable sounds funny. And Ratatouille sounds pretty funny.
Idiom is correct.
what is a idiom about a cat
In an attempt to sound more intelligent, the bumbling speaker looked more like an imbecile using words incorrectly.
"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.
"Larger than life" is an idiom, so there isn't an idiom for it.
It is a idiom.
Coinage could be accurately described as neology.The recent coinage of the word redonkulous is suspect.