Meaning of diagraph

di•a•graph

Pronunciation: (dī'u-graf", -gräf"), [key]
— n.
  1. a device for drawing, used in reproducing outlines, plans, etc., mechanically on any desired scale.
  2. a combined protractor and scale.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.