cygnet vs swan

cygnet and swan both are nouns.

Word	Noun	Adjective	Verb	Adverb
cygnet	Yes	No	No	No
swan	Yes	No	Yes	No

As nouns, swan is a hypernym of cygnet; that is, swan is a word with a broader meaning than cygnet:

cygnet: a young swan
swan: stately heavy-bodied aquatic bird with very long neck and usually white plumage as adult

Other hypernyms of cygnet include young bird.

cygnet (noun)	swan (noun)
a young swan	stately heavy-bodied aquatic bird with very long neck and usually white plumage as adult

cygnet (verb)	swan (verb)
	to declare or affirm solemnly and formally as true
	move about aimlessly or without any destination, often in search of food or employment
	sweep majestically