D defs.my
Entry 4 senses Webster, 1913

Trigon

· Tri·gon · IPA /ˈtɹaɪɡɒn/
01 n. A figure having three angles; a triangle.
  1. 1.
    A figure having three angles; a triangle.
  2. 2.
    A division consisting of three signs.(Astrol.)
  3. 3.
    A kind of triangular lyre or harp.(Gr. & Rom. Antiq.)
  4. 4.
    The cutting region of the crown of an upper molar, usually the anterior part. That of a lower molar is the Tri"go*nid (�).(Zool.)