Douglas Harper's Etymology Dictionary
lyso-
word-forming element indicating "loosening, dissolving, freeing," before vowels lys-, from comb. form of Greek lysis "a loosening" (see lyse).
Wikipedia
Lyso-
Lyso- is a prefix applied to the various phospholipids to indicate the removal of one of the two fatty acids. For example, lysophosphatidylcholines are phosphatidylcholines with a single acyl group in either the 1- or 2-position.
Category:Chemistry prefixes