Definition of "rennin" [ren•nin]

• An enzyme that catalyzes the coagulation of milk, found in the gastric juice of the fourth stomach of young ruminants and used in making cheeses and junkets. Also called chymosin, rennet. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "In the stomach of small children, especially infants an enzyme called rennin plays an important role."
• "An enzyme called rennin exists in the gastric juice of the human stomach also."
• "Digestive enzymes in fish stomach is similar to rennin which is found in the rumen of cattle."