Synonyms for Phase (same or very similar meaning)
WordNet sense 1 (any distinct time period in a sequence of events):
stageWordNet sense 2 (a particular point in the time of a cycle; measured from some arbitrary zero and expressed as an angle):
phase angleWordNet sense 3 ((physical chemistry) a distinct state of matter in a system; matter that is identical in chemical composition and physical state and separated from other material by the phase boundary):
formFrom the ODE community, based on WordNetadd/edit