holiday vs picnic

holiday and picnic both are nouns.

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

As nouns, picnic is a hyponym of holiday; that is, picnic is a word with a more specific, narrower meaning than holiday:

Other hyponyms of holiday include half-term, vac, vacay, field day, outing, honeymoon, paid vacation, winter break.

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

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