Idioms
An idiom is a widely used saying or expression containing a figurative meaning that differs from the phrase's literal meaning.
Idiom:
know what's what
Meaning:
to know the facts about something
Example:
It is difficult to know what's what with the man's problem.
List of common idioms, their meanings and examples of their usage in sentences
The language peculiar to a people or to a district, community, or class