What is "plasmalogen"

n. (context organic chemistry English) Any of a class of phospholipids, found in cell membranes, in which one of the fatty acids is replaced by an aldehyde (connected to the glycerol with an unsaturated ether linkage)

Plasmalogens are a type of ether phospholipid characterized by the presence of a vinyl ether linkage at the sn-1 position and an ester linkage at the sn-2 position. In mammals, the sn-1 position is typically derived from C16:0, C18:0, or C18:1 fatty alcohols while the sn-2 position is most commonly occupied by polyunsaturated fatty acids (PUFAs). The most common head groups present in mammalian plasmalogens are ethanolamine (designated plasmenylethalomines) or choline (designated plasmenylcholines).