kəˈlästrəm noun
( -s )
Etymology: Latin, beastings
: a specialized secretion of the mammary glands that is produced during the first few days after parturition, that differs from typical milk in its higher content of protein (as albumin and globulins) and antibodies, vitamins, and minerals and its lower content of sugars and fats, and that supplies essential immune bodies to the young animal and aids in the establishment of the intestinal function