Word by Word Definitions
: the angle bounded by two lines perpendicular to each other : an angle of 90° or ¹/₂ π radians
: a polygon having three sides — compare spherical triangle
: a percussion instrument consisting of a rod of steel bent into the form of a triangle open at one angle and sounded by striking with a small metal rod
: a drafting instrument consisting of a thin flat right-angled triangle of wood or plastic with acute angles of 45 degrees or of 30 degrees and 60 degrees
Seen and Heard
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