chat show vs broadcast

chat show and broadcast both are nouns.

Word	Noun	Adjective	Verb	Adverb
chat show	Yes	No	No	No
broadcast	Yes	No	Yes	No

As nouns, broadcast is a hypernym of chat show; that is, broadcast is a word with a broader meaning than chat show:

chat show: a program during which well-known people discuss a topic or answer questions telephoned in by the audience
broadcast: a radio or television show

Other hypernyms of chat show include program, programme.

chat show (noun)	broadcast (noun)
a program during which well-known people discuss a topic or answer questions telephoned in by the audience	message that is transmitted by radio or television
	a radio or television show

chat show (verb)	broadcast (verb)
	cause to become widely known
	broadcast over the airwaves, as in radio or television
	sow over a wide area, especially by hand