Plural of bullbat, another name for the nightjar bird, which makes a booming sound similar to a bull and hunts insects at dusk and night.
From 'bull' (large bovine animal whose deep sounds are distinctive) + 'bat' (the flying animal, or possibly from the bird's erratic flight pattern resembling a bat). The name mimics both the bird's sound and its nighttime aerial behavior.
Despite their name, bullbats aren't bats at all—they're birds that fooled early colonists in America who heard their strange booming calls at night and assumed they were some hybrid creature. This word is a perfect example of how folk nomenclature creates confusion that sticks around for centuries.
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