The definition of Trinity came after the preisthood of the Lord was removed off the earth!
It is a was arrived at the concencus of men!
There is the word Godhead in the scriptures but NO Trinity!
Of course there are many terms in theology that are not in scripture; that’s somewhat the point of theology or exegesis in general.
This applies to all religions’ theology.
As far as a scriptural basis for the Trinity, there are many. A couple of quick ones:
Matthew 3:13-17
Then cometh Jesus from Galilee to Jordan unto John, to be baptized of him. But John forbad him, saying, I have need to be baptized of thee, and comest thou to me? And Jesus answering said unto him, Suffer it to be so now: for thus it becometh us to fulfil all righteousness. Then he suffered him. And Jesus, when he was baptized, went up straightway out of the water: and, lo, the heavens were opened unto him, and he saw the Spirit of God descending like a dove, and lighting upon him: And lo a voice from heaven, saying, This is my beloved Son, in whom I am well pleased.
And the Great Commission to evangelize is clear in naming the Three Persons:
Matthew 28:19
Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit.
thanks for your reply..