: the point or stage in a period of uniform circular motion, harmonic motion, or the periodic changes of any magnitude varying according to a simple harmonic law to which the rotation, …

A phase is one of the forms in which matter can exist, such as solid, liquid, or a gas.

1. any distinct or characteristic period or stage in a sequence of events or chain of development: there were two phases to the resolution; his immaturity was a passing phase.

Nov 28, 2025 · (astronomy) A particular appearance or state in a regularly recurring cycle of changes with respect to quantity of illumination or form, or the absence, of a body's illuminated …

Meaning "to carry out gradually" is from 1949, hence phase in "introduce gradually" (1954), phase out "take out gradually in planned stages" (1954). Related: Phased; phasing.

phase, n.² meanings, etymology, pronunciation and more in the Oxford English Dictionary

a stage in a process of change or development: Each phase of life brings its own joys. a side, aspect, or point of view: This is only one phase of the question.

Phase definition: A distinct stage of development.

Phase definition: any of the major appearances or aspects in which a thing of varying modes or conditions manifests itself to the eye or mind.. See examples of PHASE used in a sentence.

Sep 25, 2025 · The other side of the Moon is dark. The position of the Moon and the Sun during Each of the Moon’s phases and the Moon as it appears from Earth during each phase. Credit: …