grain vs cereal

grain and cereal both are nouns.

Word	Noun	Adjective	Verb	Adverb
grain	Yes	No	Yes	No
cereal	Yes	Yes	No	No

As nouns, grain and cereal are synonyms defined as:

grain and cereal: foodstuff prepared from the starchy grains of cereal grasses

Other synonyms of grain include food grain.

As nouns, cereal is a hypernym of grain; that is, cereal is a word with a broader meaning than grain:

grain: a cereal grass
cereal: grass whose starchy grains are used as food: wheat, rice, rye, oats, maize, buckwheat, millet

Other hypernyms of grain include cereal grass.

grain (noun)	cereal (noun)
the direction, texture, or pattern of fibers found in wood or leather or stone or in a woven fabric	a breakfast food prepared from grain
the physical composition of something (especially with respect to the size and shape of the small constituents of a substance)	foodstuff prepared from the starchy grains of cereal grasses
the smallest possible unit of anything	grass whose starchy grains are used as food: wheat, rice, rye, oats, maize, buckwheat, millet
foodstuff prepared from the starchy grains of cereal grasses
a relatively small granular particle of a substance
dry seed-like fruit produced by the cereal grasses: e.g. wheat, barley, Indian corn
a cereal grass
1/7000 pound; equals a troy grain or 64.799 milligrams
1/60 dram; equals an avoirdupois grain or 64.799 milligrams
a weight unit used for pearls or diamonds: 50 mg or 1/4 carat
the side of leather from which the hair has been removed

grain (adjective)	cereal (adjective)
	made of grain or relating to grain or the plants that produce it

grain (verb)	cereal (verb)
form into grains
become granular
thoroughly work in
paint (a surface) to make it look like stone or wood