Idioms are phrases which cannot be understood simply by looking at the meaning of the individual words in the phrase.
Idiom:
sing a different tune
Meaning:
to contradict one's previous ideas, to change one's attitude
Example:
Usually the man does not care if he disturbs his neighbors at midnight but now that he must get up early in the morning he is singing a different tune.
List of common idioms, their meanings and examples of their usage in sentences
An idiom is a type of phrase or expression that has a meaning that can't be deciphered by defining the individual words.