Surely one of Endor's most vicious insects, the rare but often lethal Hummerhorn ("Huilokir") was the stuff of legend. Each weighed 6-8 lbs and had a razor sharp, pointed proboscis of chitin (transparent horn). It gored a victim to death, then feasted on the corpse with three sets of mandibles. They resembled gigantic black and grey hornets or wasps, and their only failing was the humming noise they made whenever they approached.
The term "hummerhorns" seems to be a hobbitish pun on "humming hornets".The diminuitive protagonist of the hobbit poem "errantry" battles only relatively harmless small insects such as honeybees, bumblebees and "humming hornets".