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3rd Grade

A line that connects two opposite corners of a figure.


From Latin, from Greek dia-, 'apart' or 'across' + -gon, 'angle,' meaning 'from angle to angle.' Greek -gon derives from Indo-European genu-, 'knee, angle'.

Related mathematical terms

* For terms related to -gon, see: Orthogonal, -gon, Pentagon, Hexagon, Octagon, Trigonometry

* For terms related to -dia, see: Diameter

Other related words

knee (the kn of knee is the gn of genu in genuflect), kneel, genuflect, genuine (sworn as truth on bended knee!), -gon (in orthogonal where ortho- means 'right'; pentagon, hexagon, etc.)