Pronunciation: (trin"i-târ'ē-un),[key] —adj. 1. believing in or adhering to the doctrine of the Trinity.
2. pertaining to Trinitarians, or believers in the doctrine of the Trinity.
3. belonging or pertaining to the religious order of Trinitarians.
4. of or pertaining to the Trinity.
5. (l.c.) forming a trinity; threefold; triple.
—n. 1. a person who believes in the doctrine of the Trinity.
2. a member of the “Order of the Holy Trinity,” a religious order founded in 1198 to redeem Christian captives of the Muslims.