In Arabic it means “defender, companion,...") is related?

I doubt it. Arabic descends from a (reconstructed) Proto-Semitic (as do Hebrew, Aramaic, and Amharic). Proto-Indo-Eruopean is reconstructed from the various Indo-European languages. To go back farther is probably not possible. (Although some have tried. You might look for a Nostratic forum to ask.) It's probably just a chance similarity.

Ceci n'est pas un seing.