English has many euphemisms for natural functions like going to the toilet. When nature calls is one. Going to the bathroom, or going to the little room are two more. 

Thanks for all of your comment and interpretation.

Ben

Warren

AnthonynewJersey

Peachey

Steveh

Thanks

ENGLISH language is interesting for me

I think my language hasn't this kind of equal words for this word

We have toilet men/ toilet women

Yes, exactly that.  We could add a few more euphemisms, like...

See a man about a dog

Spend a penny

Powder one's nose (females)

Get a touch of the trots (this is an emergency situation)

If you need to urinate, then you need to either "go number one" or "take a p*ss". 

If you were to have a bowel movement, then you need to either "go number two" or "take a sh*t."