Origin: Du donderbus < donder, thunder + bus, gun (orig., box or tube): altered by assoc. with blunder
See blunderbuss in American Heritage Dictionary 4
Origin: Alteration of Dutch donderbus
Origin: : donder, thunder (from Middle Dutch doner; see (s)tenə- in Indo-European roots)
Origin: + bus, gun (from Middle Dutch busse, tube, from Latin buxis, box; see box1).
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