What is not absorbable; specifically (Physiol.), not capable of absorption; unable to pass by osmosis into the circulating blood; as, the unabsorbable portion of food called?

unabsorbable — Not absorbable; specifically (Physiol.), not capable of absorption; unable to pass by osmosis into the circulating blood; as, the unabsorbable portion of food. (Webster's 1913.)

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