Idioms are phrases which cannot be understood simply by looking at the meaning of the individual words in the phrase.
Idiom:
lay it on thick
Meaning:
to praise someone too much
Example:
My friend began to lay it on thick when I told him about my new job.
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.