cephalin

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of a group of phospholipids having hemostatic properties and found especially in the white matter of the brain and spinal cord.

from The Century Dictionary.

• noun One of a group of organic phosphorized bodies obtained by Thudichum from brain tissue.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Physiol. Chem.) One of a group of phospholipids (nitrogenous phosphorized fatty substances), present in all living cells and particularly evident in nervous tissue. The cephalins consist of glycerol phosphate in which the two free hydroxyls of the glycerol are esterified with fatty acids, and the phosphate forms an ester linkage to the hydroxyl of ethanolamine. The phosphate may be linked to the alpha (end) or beta (middle) hydroxyl of the glycerol portion. The natural isomers are of the alpha form, and have the general formula R.O.CH2.CHOR′.CH2.O.PO2.O.CH2.CH2.NH2, where R and R′ are the acyl residues of long-chain fatty acids, which may be the same or different.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun biochemistry a phospholipid found particularly in the cells of nervous tissue; it is also the primary phospholipid in bacteria