wullacken.

From Westphalian Low German wulla(c)ken (attested 19th c. or earlier), also walla(c)ken and, without the velar element, wullen. All of these have the sense “to beat, brawl” besides “to toil”. Perhaps most plausibly a corruption of buerwiärken, from Middle Low German bûrwerken (“to perform obligatory services in public construction, groundworks etc.”), derived from bûr (“citizen, burgher, villager, farmer”) + werken (“to work”). Compare the byform bollwiärken (“to toil”), which was influenced by the noun at hand in English bulwark. The Westfälisches Wörterbuch also attests a form bullackern, which may reflect an intermediate step of the further development. Other possible connections These include: * Low German wöhlen, German wühlen (“to dig, rummage”); * Low German Wull, German Wolle (“wool”), either through the noun Wullaken (“firm fabric of wool and flax”), or as in sich in die Wolle kriegen (“to brawl, fight”); * Low German Wallack, German Wallach (“gelding”, hence “working horse”); * (Low) German walken (“to waulk, full, beat”); * (Low) German ackern (“to toil”), from Acker (“field, agricultural land”). Note that even if the derivation from buer-, bollwiärken is correct, some of these influences may explain the phonetic form, especially the initial w-.