The name Jehovah
This pronounceable form of YHWH was introduced in 1520 by Galatinus but immediately strongly contested. Because the Hebrew script almost only consists of consonants, the vowels had to be inserted when the text was read out loud. When the language ceased to be used, the Masoretes devised an ingenious vowel-notation system to preserve the pronunciation.
However, the name YHWH was deemed so holy that it shouldn't be pronounced. In stead, the reader would say אדוני (adonai), meaning My Lord, from the unused and not translatable root אדון ('adon). Another derivation of this same root is the noun אדן ('eden a, not to be confused with עדן, the name Eden), meaning pedestal.
Hence the Masoretes superimposed the vowel-notation of אדוני onto יהוה and the word Jehovah was born.