Merriam-Webster Collegiate Dictionary - lysis

 noun combining form  (plural -lyses)  Etymology: New Latin, from Latin & Greek; Latin, loosening, from Greek, from lysis  1. decomposition electrolysis  2. disintegration ; breaking down autolysis LYSIS  noun  (plural lyses)  Etymology: New Latin, from Greek, act of loosening, dissolution, remission of fever, from lyein to loosen — more at lose  Date: 1543  1. the gradual decline of a disease process (as fever)  2. a process of disintegration or dissolution (as of cells)