An Etymological Dictionary of the German Language/Werk
Werk, n., ‘work, deed, production,’ from the equiv. MidHG. wërc (wërch), OHG. wërc, wërah (hh), n.; for the double forms comp. the cognate Werg. Based on a common Teut. werko-, ‘work,’ which is attested by OIc. verk, AS. weorc, E. work, Du. and OSax. wërk. For further details concerning the root, to which Gr. ἔργον is allied, see wirken.