seinetwegen

Etymology
Shortened from, which can be traced through two developmental routes. One route is from, from , from , in which was the dative plural of modern-day  and  was the possessive pronoun in the dative plural.

Another route can be traced from, from , from , in which was the genitive pronoun. See more at.

Adverb

 * 1) because of him, for his sake
 * 2) as far as he is concerned (he doesn't mind if); for all he cares
 * 1) as far as he is concerned (he doesn't mind if); for all he cares
 * 1) as far as he is concerned (he doesn't mind if); for all he cares