- any distinct time period in a sequence of events
- (physical chemistry) a distinct state of matter in a system
- a particular point in the time of a cycle
- (astronomy) the particular appearance of a body's state of illumination (especially one of the recurring shapes of the part of Earth's moon that is illuminated by the sun)
💬 Examples
- "we are in a transitional stage in which many former ideas must be revised or rejected"
- "matter that is identical in chemical composition and physical state and separated from other material by the phase boundary"
- "the reaction occurs in the liquid phase of the system"
- "measured from some arbitrary zero and expressed as an angle"