An idiom is a group of words, or in other words, a phrase that has a meaning different from the literal meaning of the words in it.
Idiom:
with a vengeance
Meaning:
with determination and eagerness
Example:
The basketball team played with a vengeance and won the game easily.
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.