white-headed stilt vs stilt

white-headed stilt and stilt both are nouns.

Word	Noun	Adjective	Verb	Adverb
white-headed stilt	Yes	No	No	No
stilt	Yes	No	No	No

As nouns, stilt is a hypernym of white-headed stilt; that is, stilt is a word with a broader meaning than white-headed stilt:

white-headed stilt: stilt of the southwest Pacific including Australia and New Zealand having mostly white plumage but with black wings and nape of neck
stilt: long-legged three-toed black-and-white wading bird of inland ponds and marshes or brackish lagoons

Other hypernyms of white-headed stilt include Himantopus stilt, long-legs, longlegs, stilt plover, stiltbird.

white-headed stilt (noun)	stilt (noun)
stilt of the southwest Pacific including Australia and New Zealand having mostly white plumage but with black wings and nape of neck	long-legged three-toed black-and-white wading bird of inland ponds and marshes or brackish lagoons
	long-legged three-toed wading bird of brackish marshes of Australia
	one of two stout poles with foot rests in the middle; used for walking high above the ground
	a column of wood or steel or concrete that is driven into the ground to provide support for a structure