Tetragrammaton

n. (in Greek) meaning "four letters"; four Hebrew letters that are usually written or spelled in the alphabet of another language as YHWH (Yaweh) or JHVH (Jehovah) that form a biblical name of God, Hebrew name for God

Yahweh is a proposed English reading of , the name of the God of Israel, as preserved in the original consonantal Hebrew Bible text. These four Hebrew letters [ i.e. ] are often collectively called the Tetragrammaton (from the Greek , meaning 'four-letter [word]'), and are usually transliterated JHWH in German, and either YHWH, YHVH, JHWH or JHVH in English.
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Noun
1. four Hebrew letters usually transliterated as YHWH (Yahweh) or JHVH (Jehovah) signifying the Hebrew name for God which the Jews regarded as too holy to pronounce
(hypernym) tetragram

(n.)
The mystic number four, which was often symbolized to represent the Deity, whose name was expressed by four letters among some ancient nations; as, the Hebrew JeHoVaH, Greek qeo`s, Latin deus, etc.
  

[Judaic] Greek: "Four letters". The four letters which compose the name of God. Traditionally the name is so sacred that it is never articulated and the letters YHWH are read in the text as Adonai or Ha-Shem. In English the tetragrammaton is sometimes pronounced as Jehova.