Trinity (noun)

1. The state of being three in one, specifically, the Christian doctrine of the Father, Son, and Holy Spirit being one in essence and equal in authority.
2. A group of three people or things.

Origin:

From old english triniti, trinite, from latin trinitas, from trini ("three eac.h")

Examples:

1. The trinity is an important concept in Christian theology.
2. The Holy Trinity is considered to be three divine persons in one Godhead.
3. In mathematics, the trinity of points is used to describe a triangle.
4. The trinity of authors produced a collection of short stories that received critical acclaim.
5. The trinity of muses inspired artists and poets throughout the ages.