Definition of "trinity" []

• A group consisting of three closely related members. Also called triunity. (noun)
• Theology In most Christian faiths, the union of three divine persons, the Father, Son, and Holy Spirit, in one God. Also called Trine. (noun)
• Trinity Sunday. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The Bible does not contain the term trinity either, but repeatedly it refers to the “threeness” of God being God the Father, the Son, and the Holy Spirit."
• "Although the term trinity is a theological expression devised by the early Church Fathers in countering various heresies, such as Gnosticism, Sabellianism, and Arianism, and not to be found explicitly in the Bible, it is everywhere assumed and alluded to."
• "Though the term trinity isn’t in the Bible, the truth of God’s three-in-one nature is."