Trinitarian

1. n. One of a monastic order founded in Rome in 1198 by St. John of Matha, and an old French hermit, Felix of Valois, for the purpose of redeeming Christian captives from the Mohammedans.
2. a. Of or pertaining to the Trinity, the doctrine of the Trinity, or believers in that doctrine.
3. n. One who believes in the doctrine of the Trinity.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.