2. (Science: ornithology) Any one of numerous species of small, long-winged, insectivorous birds of the family Micropodidae. In form and habits the swifts resemble swallows, but they are destitute of complex vocal muscles and are not singing birds, but belong to a widely different group allied to the humming birds.
The common European swift (Cypselus, or Micropus, apus) nests in church steeples and under the tiles of roofs, and is noted for its rapid flight and shrill screams. It is called also black martin, black swift, hawk swallow, devil bird, swingdevil, screech martin, and shreik owl. The common American, or chimney, swift (Chaetura pelagica) has sharp rigid tips to the tail feathers. It attaches its nest to the inner walls of chimneys, and is called also chimney swallow. The Australian swift (Chaetura caudacuta) also has sharp naked tips to the tail quills. The European alpine swift (Cypselus melba) is whitish beneath, with a white band across the breast. The common indian swift is Cypselus affinis. See also palm swift, and tree swift.
winding yarn, thread, etc.; used chiefly in the plural.