silk hat vs hat

silk hat and hat both are nouns.

Word	Noun	Adjective	Verb	Adverb
silk hat	Yes	No	No	No
hat	Yes	No	Yes	No

As nouns, hat is a hypernym of silk hat; that is, hat is a word with a broader meaning than silk hat:

silk hat: a man's hat with a tall crown; usually covered with silk or with beaver fur
hat: headdress that protects the head from bad weather; has shaped crown and usually a brim

Other hypernyms of silk hat include chapeau, lid, man's clothing.

silk hat (noun)	hat (noun)
a man's hat with a tall crown; usually covered with silk or with beaver fur	an informal term for a person's role
	headdress that protects the head from bad weather; has shaped crown and usually a brim

silk hat (verb)	hat (verb)
	put on or wear a hat
	furnish with a hat