The sleeves of a coat, shirt, or other item of clothing are the parts that cover your arms.

A record sleeve is the stiff envelope in which a record is kept.

If someone wears their heart on their sleeve, they behave in a way that makes their feelings very obvious, for example when they are in love with someone.

If you have something up your sleeve, you have an idea or plan which you have not told anyone about. You can also say that someone has an ace, card, or trick up their sleeve .