straightedge /ˈstreɪtˌɛʤ/ noun plural straightedges
plural straightedges
Learner's definition of STRAIGHTEDGE
[count]
: a piece of wood, metal, plastic, etc., with a straight edge that you use to make sure something (such as a line or surface) is straight or to make straight lines or cuts（校正或绘制直线用的）直尺，标尺