Adam Clarke on Psalms 109:6

Let Satan stand at his right hand - As the word שטן satan means an adversary simply, though sometimes it is used to express the evil spirit Satan, I think it best to preserve here its grammatical meaning: "Let an adversary stand at his right hand:" i.e., Let him be opposed and thwarted in all his purposes.

All the Versions have devil, or some equivocal word. The Arabic has eblees, the chief of the apostate spirits; but the name is probably corrupted from the Greek διαβολος diabolos; from which the Latin diabolus. the Italian diavolo, the Spanish diablo, the French diable, the Irish or Celtic diabal, the Dutch duivel, the German teufel, the Anglo-Saxon deofal, and the English devil, are all derived. The original, διαβολος, comes from δια βαλλειν to shoot or pierce through.