I did not ask how Trinitarians interpret "only true God", I asked what that phrase means to you since I know how "only true God" is interpreted to support the Trinity. Now John wrote that Jesus prayed to the Father and said of the Father that He is the "only true God".
As to your question regarding John 1:14, I have addressed this on multiple threads you have posted to. In Colossians 1:15 the Son is referred to as the first-born of all creation, Peter says of the Son in Acts 2:
Acts 2:23
23 this Man, delivered up by the predetermined plan and foreknowledge of God, you nailed to a cross by the hands of godless men and put Him to death. NAS
In Hebrews 1 the author quotes Psalm 2
6 "But as for Me, I have installed My King
Upon Zion, My holy mountain."
7 "I will surely tell of the decree of the LORD:
He said to Me, 'Thou art My Son,
Today I have begotten Thee.
Now lets go back to John 1:
John 1:18
18 No one has seen God at any time. The only begotten Son, who is in the bosom of the Father, He has declared Him. NKJV
Yes, I remember our prior debate that involved the meaning of "love your neighbor as yourself" and how mainline Christianity treats the gay community. If mainline Christianity had obeyed the Lord we might have avoided the current normalization of homosexuality.