Jehovah vs Yahweh

Jehovah

name
  • The personal name of God in the Hebrew Scriptures; in Hebrew, יהוה (YHVH) 

noun
  • A Jehovah's Witness. 

Yahweh

name
  • The name of the God of Israel worshipped by the Jahwist prophets in the kingdoms of Israel and Judah in antiquity. 

  • In "Sacred Name Bibles", the transliteration of the Tetragrammaton. 

How often have the words Jehovah and Yahweh occurred in a corpus of books? (source: Google Ngram Viewer )