Dumbledors are a kind of winged insect.
The Dumbledor are only mentioned in the Hobbit poem, Errantry in The Adventures of Tom Bombadil, which describes them as ferocious winged insects. Their origin and history have been lost to Men.
They are stated as being nasty insects that live in bogs and marshlands around the Shire. They are somewhat similar to Neekerbreekers, also mentioned in Hobbit-lore.
Behind the ScenesEdit
The word Dumbledor is very similar to Albus Dumbledore, a character from J.K. Rowling's Harry Potter series.