soymilk vs soybean milk

soymilk and soybean milk both are nouns.

Word	Noun	Adjective	Verb	Adverb
soymilk	Yes	No	No	No
soybean milk	Yes	No	No	No

As nouns, soymilk and soybean milk are synonyms defined as:

soymilk and soybean milk: a milk substitute containing soybean flour and water; used in some infant formulas and in making tofu

Other synonyms of soymilk include soya milk.

soymilk (noun)	soybean milk (noun)
a milk substitute containing soybean flour and water; used in some infant formulas and in making tofu	a milk substitute containing soybean flour and water; used in some infant formulas and in making tofu