change of state
process, event, or action modifying relatively stable qualities of a subject
phase change
transitions between solid, liquid and gaseous states of matter, and, in rare cases, plasma
liquefaction
process which either generates a liquid from a solid or a gas, or generates a non-liquid phase which behaves in accordance with fluid dynamics
dying
final process of life
spontaneous emission
quantum mechanical state change
Critical transition
abrupt shift in a complex dynamic system