trinitarian, a. [Cf. F. trinitaire. See Trinity.].
Of or pertaining to the Trinity, the doctrine of the Trinity, or believers in that doctrine. [1913 Webster]
trinitarian, n.
One who believes in the doctrine of the Trinity. [1913 Webster]
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 Moslems. [1913 Webster]