Definition of set square in US English:

set square


  • 1A right-angled triangular plate for drawing lines, especially at 90°, 45°, 60°, or 30°.

    • ‘All that was being said was something dreadfully boring involving the importance of set squares.’
    • ‘Tomorrow will be taken up with preparing for the Big Day itself, namely, preparing my desk, purchasing a set square and compass and making a list.’
    • ‘On the lower shelf are two books (a hymn book and a merchant's arithmetic book), a lute, a terrestrial globe, a case of flutes, a set square, and a pair of dividers.’
    • ‘It was here that Burlington kept his collection of architectural plans and the painting on the ceiling reflects this interest through the personification of the subject, surrounded by set squares and plumb lines.’
    • ‘Almost everyone has used a calculator or a set square during their school days.’
    1. 1.1 A form of T-square with an additional arm turning on a pivot for drawing lines at fixed angles to the head.
      • ‘They used iron chisels, saws, drills, and callipers, set squares and plumb lines.’
      • ‘If any architects or firms have redundant T squares and set squares, and books and journals they can spare, these would be gratefully received.’


set square

/ˈsɛt ˌskwɛ(ə)r//ˈset ˌskwe(ə)r/