dumble-comb. form
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Stress is often attracted to this element and vowels may be reduced accordingly; see e.g.
dumbledore n.Origin: Of uncertain origin. Probably an imitative or expressive formation.
Etymology: Origin uncertain; probably ultimately imitative of a buzzing, droning, or humming sound. Compare bumble v.1, drumble- comb. form, humble v.2, and perhaps also Old English -dumbla (in rāradumbla : see mire-drum n., and compare the Germanic compounds cited at that entry).This combining form is only attested in a small number of insect names: see dumble bee n. and dumbledore n. dummel adj. is unlikely to be related on semantic grounds.
This entry has not yet been fully updated (first published 1897; most recently modified version published online December 2020).