| big brown bat | (n) rather large North American brown bat; widely distributed, Syn. Eptesicus fuscus |
| brown bat | (n) any of numerous medium to small insectivorous bats found worldwide in caves and trees and buildings |
| little brown bat | (n) the small common North American bat; widely distributed, Syn. Myotis leucifugus, little brown myotis |
| serotine | (n) common brown bat of Europe, Syn. Eptesicus serotinus, European brown bat |