# D valve

> English word · Noun

## Definitions
1. A slide valve with a cup-like cavity in its face, through which exhaust steam passes.

## Etymology
Named after the hollow central D-sectioned piston.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/d-valve