A cap (normally plastic) which is provided with some open-top cans and is used to cover the open end once the can has been opened. This term is also used to describe a cap which is used to cover the primary closure, sprayer or other dispensing system such as finger tip sprayer or aerosol valve.

A cap (usually plastic) provided with some cans. It is used to cover the open end once the can has been opened. Sometimes, it is used to describe a cap that is used to cover the primary closure or other dispensing system, such as a fingertip sprayer or aerosol valve.