soy flour vs soybean flour

soy flour and soybean flour both are nouns.

Word	Noun	Adjective	Verb	Adverb
soy flour	Yes	No	No	No
soybean flour	Yes	No	No	No

As nouns, soy flour and soybean flour are synonyms defined as:

Other synonyms of soy flour include soybean meal.

soy flour (noun)	soybean flour (noun)
meal made from soybeans	meal made from soybeans