What is a characteristic of an 'idiom'?

An idiom is a phrase or expression that has a figurative meaning that differs from its literal interpretation. This characteristic is what sets idioms apart from standard phrases; understanding their meaning often requires familiarity with the culture or context in which they are used. For example, the idiom "kick the bucket" means to die, which is not related to kicking a physical bucket but rather invokes a different concept altogether. This reliance on a non-literal interpretation underlines why the choice conveying a figurative meaning is the correct characteristic of an idiom.