jazz festival vs festival

jazz festival and festival both are nouns.

Word	Noun	Adjective	Verb	Adverb
jazz festival	Yes	No	No	No
festival	Yes	No	No	No

As nouns, festival is a hypernym of jazz festival; that is, festival is a word with a broader meaning than jazz festival:

jazz festival: a festival that features performances by jazz artists
festival: an organized series of acts and performances (usually in one place)

Other hypernyms of jazz festival include fete.

jazz festival (noun)	festival (noun)
a festival that features performances by jazz artists	an organized series of acts and performances (usually in one place)
	a day or period of time set aside for feasting and celebration