dor

From Middle English dorre, dore, from Old English dora (“humming insect”), from Proto-West Germanic *dorō, from Proto-Germanic *durô (“bumblebee, humming insect”), from Proto-Indo-European *dʰer-, *dʰreh₁n- (“bee, hornet, drone”). Related to Saterland Frisian Doarne (“hornet”), Middle Low German dorne (“bumblebee”), Middle Dutch dorne (“bumblebee”), Dutch dar (“drone”), Old English drān (“drone”). More at drone.

Compare dor (“a beetle”), and hum, humbug.