According to Star Wars creator George Lucas, he experimented with various combinations of names for the character built upon the phrase "Dark Water". Then he "added lots of last names, Vaders and Wilsons and Smiths, and ... just came up with the combination of Darth and Vader". After the release of The Empire Strikes Back (1980), Lucas stated that the name Vader was based upon the German/Dutch-language word Vater or vader, meaning 'father', making the name representative of a "Dark Father.
So not sure if there is a equivalent of German/Dutch in the Star Wars Universe but George Lucas deliberately named him so.
Out of universe George named him not the force, in universe I am not sure.
Or maybe everything that George Lucas said was a lie.Or maybe everything that George Lucas said was a lie.