n. (Zool.), any bird of the family Trochilidæ, of which over one hundred genera are known, including about four hundred species. They are found only in America and are most abundant in the tropics. They are mostly of very small size with long slender bills adapted to sucking nectar from flowers, and are noted for the very brilliant iridescent colors of their plumage and their peculiar habit of hovering about flowers while vibrating their wings very rapidly with a humming noise; the wings are specialized for hovering flight, but they can also dart forward and fly quite rapidly. They feed both upon the nectar of flowers and upon small insects. The common humming bird or ruby-throat of the Eastern United States is Trochilus colubris. Several other species are found in the Western United States. See Calliope, and Ruby-throat. [ 1913 Webster ]