Yhwh
From BiblePortal Wikipedia
Yhwh [1]
Exodus 3:15 Exodus 20:7 Leviticus 24:16 Adonai GodI AmJehovahLord
In the course of the centuries the actual pronunciation of Yhwh was lost. In the Middle Ages Jewish scholars developed a system of symbols placed under and beside the onsonants to indicate the vowels. Yhwh appeared with the vowels from “Adonai” as a device to remind them to say “Adonai” in their reading of the text. A latinized form of this was pronounced “Jehovah,” but it was actually not a real word at all. From the study of the structure of the Hebrew language most scholars today believe that Yhwh was probably pronounced Yahweh ( Yah' weh ).
Mark Fountain