soymilk vs soya milk

soymilk and soya milk both are nouns.

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

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

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

Other synonyms of soymilk include soybean milk.

soymilk (noun)	soya 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