H hour

noun

: the hour set for launching a specific tactical operation

Word History

Etymology

H, abbreviation for hour

First Known Use

1918, in the meaning defined above

Time Traveler
The first known use of H hour was in 1918

Rhymes for H hour

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Browse Nearby Words

H hinge
H hour
HHS
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Cite this Entry

“H hour.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/H%20hour. Accessed 15 Jul. 2025.

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