Idiomatic Expression?

An idiom is an expression (i.e., term or phrase) whose meaning cannot be deduced from the literal definitions and the arrangement of its parts, but refers instead to a figurative meaning that is known only through common use.

http://en.wikipedia.org/wiki/Idiom

In other words, you do not mean literally what you say but other English-speaking people know what you mean.

Examples of idioms.

It’s raining cats and dogs.

Get off your high horse.

He’s in the dog house.

You will find more examples at this site:

http://www.learn4good.com/languages/evrd_idioms/id-a.htm

A Russian student who was studying English stayed with me one summer and I became more aware of our idioms and how silly they sound to foreigners. She was proud of learning the idiom “it’s raining cats and dogs.” The next time we had a hard rain she told me “it’s raining dogs and cats.” Somehow, it didn’t sound quite the same!

When she learned that a windshield could “fog up” she held up her arm and fanned it, asking “do people fog up?”

s

a meaningful one like absence makes the heart grow fonder