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M-day

[ em-dey ]
/ ˈɛmˌdeɪ /
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noun Military.
mobilization day: a day assumed by the Department of Defense as the first day of mobilization, used by the military for planning purposes.
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Origin of M-day

First recorded in 1935–40

Words nearby M-day

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use M-day in a sentence

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