An idiom is a saying or expression with a meaning that is hard to interpret because of the atypical meaning of the words included. The idiom, "Kick the bucket," for instance, means to die rather than to literally kick a bucket.
Because idioms are formed in a particular country, culture or language, their meanings are often confusing to non-native speakers. For example, American idioms are difficult for immigrants or foreign visitors to detect.
Idioms are used to describe the character of a particular language or art form. The term originated from a late 16th-century Latin and Greek words meaning "peculiarity" and "to make one's own."