chymosin vs rennin

chymosin and rennin both are nouns.

Word	Noun	Adjective	Verb	Adverb
chymosin	Yes	No	No	No
rennin	Yes	No	No	No

As nouns, chymosin and rennin are synonyms defined as:

chymosin and rennin: an enzyme that occurs in gastric juice; causes milk to coagulate

chymosin (noun)	rennin (noun)
an enzyme that occurs in gastric juice; causes milk to coagulate	an enzyme that occurs in gastric juice; causes milk to coagulate