An idiom is a type of phrase or expression that has a meaning that can't be deciphered by defining the individual words.
Idiom:
hit (someone) right between the eyes
Meaning:
to make a strong impression on someone, to surprise someone
Example:
The singer's incredible performance really hit me between the eyes.
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.