Feathers: organ composed of a supple shaft with barbs and barbules. The feathers cover the body of the bird, protecting it and maintaining its body temperature.
Down feather: the soft, first feathers that grow on a bird.
Long flexible barbs: filaments of down feathers, which are not attached to each other.
Calamus: the shaft of the feather.
Calamus or hollow shaft: hollow quill of the feather.
Rachis or rigid shaft: solid part of the shaft.
Inter locking barbs: filaments of the feather that are not soft and free.
Vane: thin flat part of the feather.
Contour feather: one of the largest feather on the edge of a bird's wing.