Himantopus mexicanus vs stilt

Himantopus mexicanus and stilt both are nouns.

Word	Noun	Adjective	Verb	Adverb
Himantopus mexicanus	Yes	No	No	No
stilt	Yes	No	No	No

As nouns, stilt is a hypernym of Himantopus mexicanus; that is, stilt is a word with a broader meaning than Himantopus mexicanus:

Himantopus mexicanus: stilt of southwestern United States to northern South America having black plumage extending from the head down the back of the neck
stilt: long-legged three-toed black-and-white wading bird of inland ponds and marshes or brackish lagoons

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

Himantopus mexicanus (noun)	stilt (noun)
stilt of southwestern United States to northern South America having black plumage extending from the head down the back of the 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