An Etymological Dictionary of the German Language/wohl

by Friedrich Kluge

wohl, adv., ‘well, probably,’ from the equiv. MidHG. wol, OHG. wola (earlier wëla), adv. from gut; corresponding to OSax. wē̆l, Du. wel, AS. wē̆l, E. well, Goth. waila. The primary meaning of this common Teut. adv. is ‘as one could wish,’ because it is derived from the root of wollen. Aryan welo-, ‘wish, desire,’ is also indicated by Sans. vára, m. and n., ‘wish, desire,’ to which váram ã (or práti váram), ‘as one could wish, as one likes,’ is allied.