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H-hour

[ eych-ouuh r, -ou-er ]
/ ˈeɪtʃˌaʊər, -ˌaʊ ər /

noun

the time, usually unspecified, set for the beginning of a planned attack.

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RELATED WORDS

climax, contingency, crisis, crossroad, crossroads, deadline, emergency, exigency, juncture, pinch, strait, target, countdown, D-day, term

Origin of H-hour

H (for hour) + hour; cf. D-day
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for h-hour

H-hour

noun

military the specific hour at which any operation commencesAlso called: zero hour
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012