🔼The name Jehoiachin in the Bible
There's only one person called Jehoiachin in the Bible. He was the son and successor of king Jehoiakim of Judah, and his mother's name was Nehushta (2 Kings 24:8). Jehoiachin was also the before last king of Jerusalem (2 Kings 24:8). The emperor Nebuchadnezzar took him to Babylon where he remained until his death (2 Kings 24:8-16).
For reasons that we now only guess at (and many do, but they're still guessing), this king is referred to by quite a few playful variations of his original name. In the book of 1 Chronicles and Esther, he is called יכניה (Jeconiah), which is the reversal of the name Jehoiachin. The prophet Jeremiah calls him כניהו (Coniah, or rather: Coniahu) in Jeremiah 22:24, 22:28 and 37:1, יהויכן (Jehoikan) in 52:31 and יכוניה (Jekoniah) in 27:20. The prophet Ezekiel calls him יויכין (Joiakin) in Ezekiel 1:2. And since he was an ancestor of Christ, he's also mentioned by Matthew, who calls him Ιεχονιας (Iechonias; Matthew 1:11).
🔼Etymology of the name Jehoiachin
The name Jehoiachin (and all variations, we may assume) consists of two elements, the first part being יה (Yah) = יהו (Yahu) = יו (Yu), which in turn are abbreviated forms of the Tetragrammaton; the name of the Lord: YHWH.
The final part of the name Jehoiachin comes from the verb כון (kun), meaning to be established or fixed:
For a meaning of the name Jehoiachin, NOBSE Study Bible Name List reads Yahweh Establishes, Jones' Dictionary of Old Testament Proper Names has The Lord Will Establish and BDB Theological Dictionary proposes Yah Appointeth.