trigons

Noun

trigon (countable and uncountable, plural trigons)

1. (countable, rare) A triangle.
2. (countable, historical) An ancient triangular harp of Oriental origin which had four strings and was often used for banquet music. Also called sabbeka, sackbut, sambuca.
3. (countable) A division consisting of three star signs.
   • The Cancer trigon is composed of Cancer, Scorpio and Pisces
4. (countable) A trine; an aspect of two planets distant 120 degrees from each other.
   • In the horoscope of Christ's nativity.[…]Whether a trigon or no, this tetragon I am sure there was.a. 1626, Bishop Andrewes, Sermon
5. (historical, uncountable) An old ball game played by three people standing in a triangular formation. (See Wikipedia's entry for the game)
6. (countable) The cusp (cutting region) of the crown of an upper molar, usually the anterior part.