M-day
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M-day
(ĕm′dā′)n.
The day on which national mobilization for war is ordered; mobilization day.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
M-day
See: times.
Dictionary of Military and Associated Terms. US Department of Defense 2005.