1.(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;
the reaction occurs in the liquid phase of the system
2.any distinct time period in a sequence of events;
we are in a transitional stage in which many former ideas must be revised or rejected
3.a particular point in the time of a cycle; measured from some arbitrary zero and expressed as an angle
4.(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);
the full phase of the moon
1.arrange in phases or stages;
phase a withdrawal
2.adjust so as to be in a synchronized condition;
he phased the intake with the output of the machine