: 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, …

Look up Phase, phase, or phases in Wiktionary, the free dictionary.

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.

Definition of phase noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

Dec 26, 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 …

Phase definition: A distinct stage of development.