Serum
Pronunciation : Se"rum
Part of Speech : n.
Etymology : [L., akin to Gr. sara curd.] (Physiol.) (a) The watery portion of certain animal fluids, as blood, milk, etc. (b) A thin watery fluid, containing more or less albumin, secreted by the serous membranes of the body, such as the pericardium and peritoneum. B
Source : Webster's Unabridged Dictionary, 1913