What is an idiom?

An idiom is indeed best defined as a language expression characteristic of a community. This means that idioms are phrases or expressions that have a figurative meaning commonly understood among the speakers of a particular language or community, rather than the literal meanings of the individual words. For example, the idiom "kick the bucket" means to die, which is not directly related to the explicit meaning of the words used. Idioms often reflect the culture, traditions, and experiences of the people who use them, making them unique to specific languages or regions.

In contrast, while idioms can be a type of figurative language, they are more specific in their usage and social context than the broader category of figurative language itself, which includes various forms of comparison and symbolism. An exaggeration refers to hyperbole, which is also a type of figurative language but distinct from idioms. Lastly, poetic devices include techniques used in poetry to enhance meaning or emotional impact, and while idioms can appear in poetry, they are not categorized strictly as a poetic device.