# H-hour

> English word · Noun

## Definitions
1. The hour at which any major event planned for the future is set to begin, as used in United States military.

## Etymology
The H stands for hour; compare D-Day.

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