Probably from Har (“horn”) + now dialectal Wëspel (“wasp”). Compare Ripuarian Wespel. This (secondary?) compound should be seen in light of German Hornisse, English hornet, whose first syllable was early on associated with horn (with which it is indeed related). The Luxembourgish word can, or could, indeed mean “hornet”, and the Luxemburger Wörterbuch names a connecting variant Hoarässel. The details of the development are very uncertain, given the wide variety of forms both within Luxembourgish and in other Germanic languages.
Harespel f (plural Harespelen)