The word zip has several meanings:

1. To move very quickly. When you zip through your homework, you finish it fast. A car might zip past you on the highway, or a hummingbird might zip from flower to flower. The word captures that sense of speed and smoothness, like something moving so fast it makes a zip sound as it passes.
2. To fasten something with a zipper. You zip up your jacket by pulling the zipper closed, or zip open your backpack to grab your lunch. The zipper itself got its name because of the zip sound it makes when you pull it.
3. Zero or nothing at all. If you scored zip on a quiz, you got nothing right. When someone has zip energy left after a long day, they're completely exhausted. Sometimes people say zilch or nada instead, meaning the same thing.

The word also appears in ZIP Code, the five-digit number that helps the post office sort mail to the right area.