T square


noun

a T-shaped ruler, used primarily in mechanical drawing, having a short crosspiece that slides along the edge of the drawing board as a guide to the perpendicular longer section in making parallel lines, right angles, etc., and as a support for triangles.

Origin of T square

First recorded in 1775–85

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019