picnic vs holiday

picnic and holiday both are nouns.

Word	Noun	Adjective	Verb	Adverb
picnic	Yes	No	Yes	No
holiday	Yes	No	Yes	No

As nouns, holiday is a hypernym of picnic; that is, holiday is a word with a broader meaning than picnic:

Other hypernyms of picnic include vacation.

picnic (noun)	holiday (noun)
any undertaking that is easy to do	leisure time away from work devoted to rest or pleasure
any informal meal eaten outside or on an excursion	a day on which work is suspended by law or custom
a day devoted to an outdoor social gathering

picnic (verb)	holiday (verb)
eat alfresco, in the open air	spend or take a vacation