In the King James Version of the bible we read,

1 In the beginning God created the heaven and the earth.

2 And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.

3 And God said, Let there be light: and there was light.

One commentator sees these verses https://www.hebrew4christians.com/Names_of_G-d/Trinity/trinity.html as a trinity of aspects of God: God the creator, Spirit of God, and Word of God. Sometime around the fourth century AD, Christian theologians needed to make Jesus part of God, and so they defind the trinity as Father, Son, and Holy Ghost (or Holy Spirit). Others have identified the trinity as Creator, Redeemed, Sanctifier,

Creator-Redeemer-Sanctifier or Creator-Liberator-Sustainer or Creato-Redeemer-Comforter

The founders of Christianity had a problem. They believed in one God but wanted to claim that Jesus was somehow a part of that God. So they threw in a third entity and called their concept a Trinity. One God with aspects called Father, Son, and Holy Ghost. Others

Trinity was name of first atomic test/bomb

trinity of elecrtron, muon, and taut

trinity of quarks

trinity off electro-magnetic, weak, and strong forces (& gravity?)

or trinity of neutrinos

or photon, gluon, and graviton