a unit of measure of the power of a lens
, equal to the power of a lens with a focal
length of one meter
Webster’s New World College Dictionary, 4th Edition. Copyright © 2010 by
Houghton Mifflin Harcourt. All rights reserved.
Word origin of 'diopter'
< L dioptra
< Gr instrument for leveling, etc. < dia-
, through + base of opsis
, sight < ops