- a very small nectar-sipping New World bird of the family Trochilidae, characterized by the brilliant, iridescent plumage of the male, a slender bill, and narrow wings, the extremely rapid beating of which produces a humming sound: noted for their ability to hover and to fly upward, downward, and backward in a horizontal position.
- any very small American bird of the family Trochilidae, having a brilliant iridescent plumage, long slender bill, and wings specialized for very powerful vibrating flight: order Apodiformes
