flour vs wheat flour

flour and wheat flour both are nouns.

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

As nouns, wheat flour is a hyponym of flour; that is, wheat flour 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
wheat flour: flour prepared from wheat

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

flour (noun)	wheat flour (noun)
fine powdery foodstuff obtained by grinding and sifting the meal of a cereal grain	flour prepared from wheat

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