Idiomatic expression and Rusticism

Idiomatic expression noun - An expression whose meanings cannot be inferred from the meanings of the words that make it up.

Rusticism and idiomatic expression are semantically related. In some cases you can replace term "Rusticism" with "Idiomatic expression", this terms are similar.

Rusticism noun - A rural idiom or expression.

Idiomatic expression and rusticism are semantically related. Sometimes you can use "Idiomatic expression" instead a noun "Rusticism".