an instrument for laying out miter joints, consisting of two straightedges joined at a 45° angle.
Origin of miter square
First recorded in 1670–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for miter square
Historical Examples of miter square
The miter-square, Fig. 201, is a try-square fixed at an angle of 45°.Handwork in Wood