meal vs picnic

meal and picnic both are nouns.

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

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

meal (noun)	picnic (noun)
the food served and eaten at one time	any undertaking that is easy to do
coarsely ground foodstuff; especially seeds of various cereal grasses or pulse	any informal meal eaten outside or on an excursion
any of the occasions for eating food that occur by custom or habit at more or less fixed times	a day devoted to an outdoor social gathering

meal (verb)	picnic (verb)
	eat alfresco, in the open air