Trin·​i·​ty | \ ˈtri-nə-tē How to pronounce Trinity (audio) \

Definition of Trinity

 (Entry 1 of 2)

1 : the unity of Father, Son, and Holy Spirit as three persons in one Godhead according to Christian dogma
2 not capitalized : a group of three closely related persons or things
3 or Trinity Sunday : the Sunday after Whitsunday observed as a feast in honor of the Trinity


geographical name
Trin·​i·​ty | \ ˈtri-nə-tē How to pronounce Trinity (audio) \

Definition of Trinity (Entry 2 of 2)

river in eastern Texas flowing southeast into Galveston Bay

Did You Know?

The nature of the Trinity (or Holy Trinity) has caused centuries of argument and division within the Christian faith. The word doesn't actually appear in the Bible itself, but the New Testament does speak of the Father, Son, and Holy Spirit together; the Father is understood as the protector of the Jews, the Son as the savior of mankind, and the Holy Spirit as the preserver of the church. Almost all the major Christian sects may be called trinitarian. The island of Trinidad is one of many places named with the Spanish translation of Trinity.

First Known Use of Trinity


13th century, in the meaning defined at sense 1

History and Etymology for Trinity


Middle English trinite, from Anglo-French trinité, from Late Latin trinitat-, trinitas state of being threefold, from Latin trinus threefold

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The first known use of Trinity was in the 13th century

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Cite this Entry

“Trinity.” Dictionary, Merriam-Webster, Accessed 26 Oct. 2020.

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