Set phrase and Usage

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

Usage and set phrase are semantically related. in turn of phrase topic. In some cases you can use "Usage" instead a noun phrase "Set phrase".

Usage noun - The act or practice of employing something for a particular purpose.

Set phrase and usage are semantically related. Sometimes you can use "Set phrase" instead a noun "Usage".