The Collaborative International Dictionary
Kerasin
Kerasin \Ker"a*sin\, n. (Physiol. Chem.) A nitrogenous substance free from phosphorus, supposed to be present in the brain; a body closely related to cerebrin.
Wiktionary
kerasin
n. (context biochemistry archaic English) A nitrogenous substance, free from phosphorus, supposed to be present in the brain, and closely related to cerebrin.