A zip or zip fastener is a device used to open and close parts of clothes and bags. It consists of two rows of metal or plastic teeth which separate or fasten together as you pull a small tag along them.

When you zip something, you fasten it using a zip.

To zip a computer file means to compress it so that it needs less space for storage on disk and can be transmitted more quickly.

If you say that something or someone zips somewhere, you mean that they move there very quickly.

If you say that someone or something has zip, you mean that they show a lot of energy and enthusiasm.