flour vs semolina

flour and semolina both are nouns.

Word	Noun	Adjective	Verb	Adverb
flour	Yes	No	Yes	No
semolina	Yes	No	No	No

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

flour: fine powdery foodstuff obtained by grinding and sifting the meal of a cereal grain
semolina: milled product of durum wheat (or other hard wheat) used in pasta

Other hyponyms of flour include plain flour, wheat flour, soy flour, soybean flour, soybean meal, rye flour.

flour (noun)	semolina (noun)
fine powdery foodstuff obtained by grinding and sifting the meal of a cereal grain	milled product of durum wheat (or other hard wheat) used in pasta

flour (verb)	semolina (verb)
convert grain into flour
cover with flour