An idiom is a widely used saying or expression containing a figurative meaning that differs from the phrase's literal meaning.
Idiom:
out of breath
Meaning:
tired and breathing quickly.
Example:
I was out of breath after running from the station.
List of common idioms, their meanings and examples of their usage in sentences
An expression in the usage of a language that is peculiar to itself either in having a meaning that cannot be derived from the conjoined meanings of its elements or in its grammatically atypical use of words.