valve

Noun

Singular valve

Plural valves

A valve lets blood go through one way but stops it when it tries to go the other way.

A valve that people can open to let water go through.

1. (countable) A valve is part of a tube that lets liquid or gas go through one way but stops it from going through the other way.

   There are four valves in the heart that let blood go in one direction but stop it from going in the other direction.

2. (countable) A valve is part of a tube that someone can open or close to let water or other things go through.

   Open this valve to let water go through the pipe.