meal vs breakfast

meal and breakfast both are nouns.

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

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

meal (noun)	breakfast (noun)
the food served and eaten at one time	the first meal of the day (usually in the morning)
coarsely ground foodstuff; especially seeds of various cereal grasses or pulse
any of the occasions for eating food that occur by custom or habit at more or less fixed times

meal (verb)	breakfast (verb)
	eat an early morning meal
	provide breakfast for