Primary (feather)
One of the outer flight feathers ('remiges') of a bird's wing, used chiefly in manoeuvring. There are usually ten primaries and they are embedded in the skin of the bird's hand. The secondary and tertiary feathers, which are shorter than the primaries, form the other group of flight feathers.From Peter Weaver's Birdwatcher's Dictionary
Copyright © 1981 by Peter Weaver