An idiom is a widely used saying or expression containing a figurative meaning that differs from the phrase's literal meaning.
Idiom:
psych (someone) out or psych out (someone)
Meaning:
to find out the real motives or intentions of someone
Example:
I tried to psych out the salesman to see how much he would sell the car for.
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.