- the number six.
- a group or series of six.
Origin of hexad
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for hexad
The hexad axis is uniterminal and all the forms are open forms.
This is the hexad axis or hexagonal axis, for which the angle of rotation is 60, or one-sixth of 360.
Perpendicular to the hexad axis are six dyad axes of two kinds and each perpendicular to a vertical plane of symmetry.
In crystals of this division of the hexagonal system the principal axis is a hexad axis of symmetry.
Here there is a plane of symmetry perpendicular to the hexad axis; there is also a centre of symmetry.
- a group or series of six
- the number or sum of six
C17: from Greek hexas, from hex six
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
- A group or series of six.
- An element or radical having a valence of six.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.