adjective Military.
  1. pertaining to or characterizing the organization of an army division into five groups, each with supporting units, geared to maneuver in keeping with the requirements of atomic warfare.

Origin of pentomic

1955–60; pent- + (at)omic Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for pentomic


  1. denoting or relating to the subdivision of an army division into five battle groups, esp for nuclear warfare

Word Origin for pentomic

C20: from penta- + atomic
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