Crest
A tuft of feathers on the upper part of the head, also called a 'horn'. Many crests can be raised or lowered according to the psychological state of the birds. They vary from the unspectacular example of the Skylark Alauda arvensis to the long wispy one found in the Lapwing Vanellus vanellus.From Peter Weaver's Birdwatcher's Dictionary
Copyright © 1981 by Peter Weaver