Both the scientific and common names derive from their often large, lance-shaped noses, greatly reduced in some of the nectar- and pollen-feeders. Because these bats echolocate nasally, this "nose-leaf" is thought to serve some role in modifying and directing the echolocation call. Similar nose-leavesare found in some other groups of bats, most notably the Old World leaf-nosed bats.
New World leaf-nosed bats are usually brown, grey, or black, although one species is white. They range in size from 4 to 13.5 cm (1.6 to 5.3 in) in head-body length, and can weigh from 7 to 200 g (0.25 to 7.05 oz). Most roost in fairly small groups within caves, animal burrows, or hollow trees, although some species aggregate in colonies of several hundred individuals. They do not hibernate, although some species have been reported to aestivate.