Suggesting Trinity "supersedes" what is in the Bible, is inaccurate. Applying a later name in a different language as a synonym to what is written in the Bible is inevitable. Unless, of course, people wish to go back to the original Hebrew, and I don't find many who do.
Do you know any other language than English? If so, you know there is no such thing as an exact translation. A translation from a picturesque language into a subjective language is an even greater challenge.
What you consider the essence of God has very much to do with this conversation. God's essence is indivisible, which is also a teaching of the Trinity--God's essence is indivisible. From there we can consider how God manifests Himself throughout scripture: As Creator, as Spirit, as Word, as Judge, as Protector, and so on. Still an indivisible essence whether He is being portrayed first as Judge, then as Protector, as Law Giver, etc. God is all these things, yet still the indivisible, One. Naming that indivisible One "Trinity" is synonymous with what is in the Bible. In fact, it emphasizes it.