verb (used with object), phased, phas·ing.

to schedule or order so as to be available when or as needed.
to put in phase; synchronize: to phase one mechanism with another.

Verb Phrases

Origin of phase

1805–15; (noun) back formation from phases, plural of phasis
Related formsphase·less, adjectivepha·sic, pha·se·al, adjectivere·phase, verb (used with object) re·phased, re·phas·ing.sub·phase, nounun·phased, adjective
Can be confusedfaze phase

Synonyms for phase Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for phase

Contemporary Examples of phase

Historical Examples of phase

  • That we pass out of this phase of being as we came into it, for Growth.

  • That consequence may be corrected in this phase of our being, or it may be carried over into the next.

  • There is nothing about the earth-life to make it the only phase of effort and probation.

  • I didn't want to go into this phase of it, but it may explain what, with your permission, I am about to do.

  • The enormous wealth of the country will soon adjust that phase of the situation.

British Dictionary definitions for phase



any distinct or characteristic period or stage in a sequence of events or chain of developmentthere were two phases to the resolution; his immaturity was a passing phase
astronomy one of the recurring shapes of the portion of the moon or an inferior planet illuminated by the sunthe new moon, first quarter, full moon, and last quarter are the four principal phases of the moon
  1. the fraction of a cycle of a periodic quantity that has been completed at a specific reference time, expressed as an angle
  2. (as modifier)a phase shift
physics a particular stage in a periodic process or phenomenon
in phase (of two waveforms) reaching corresponding phases at the same time
out of phase (of two waveforms) not in phase
chem a distinct state of matter characterized by homogeneous composition and properties and the possession of a clearly defined boundary
zoology a variation in the normal form of an animal, esp a colour variation, brought about by seasonal or geographical change
biology (usually in combination) a stage in mitosis or meiosisprophase; metaphase
electrical engineering one of the circuits in a system in which there are two or more alternating voltages displaced by equal amounts in phase (sense 5)See also polyphase (def. 1)
(in systemic grammar) the type of correspondence that exists between the predicators in a clause that has two or more predicators; for example connection by to, as in I managed to do it, or -ing, as in we heard him singing

verb (tr)

(often passive) to execute, arrange, or introduce gradually or in stagesa phased withdrawal
(sometimes foll by with) to cause (a part, process, etc) to function or coincide with (another part, process, etc)he tried to phase the intake and output of the machine; he phased the intake with the output
mainly US to arrange (processes, goods, etc) to be supplied or executed when required
Derived Formsphaseless, adjectivephasic or phaseal, adjective

Word Origin for phase

C19: from New Latin phases, pl of phasis, from Greek: aspect; related to Greek phainein to show
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for phase

1705, "phase of the moon," back-formed as a singular from Modern Latin phases, plural of phasis, from Greek phasis "appearance" (of a star), "phase" (of the moon), from stem of phainein "to show, to make appear" (see phantasm). Latin singular phasis was used in English from 1660. Non-lunar application is first attested 1841. Meaning "temporary difficult period" (especially of adolescents) is attested from 1913.


"to synchronize," 1895, from phase (n.). Meaning "to carry out gradually" is from 1949, hence phase in "introduce gradually" (1954), phase out (1954). Related: Phased; phasing.

Online Etymology Dictionary, © 2010 Douglas Harper

phase in Medicine




A characteristic form, appearance, or stage of development that occurs in a cycle or that distinguishes some individuals of a group.
A discrete homogeneous part of a material system that is mechanically separable from the rest, as is ice from water.
Any of the forms or states, solid, liquid, gas, or plasma, in which matter can exist, depending on temperature and pressure.
A particular stage in a periodic process or phenomenon such as a wave form or time pattern.


To introduce, one stage at a time.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

phase in Science



Any of the forms, recurring in cycles, in which the Moon or a planet appears in the sky.
One of a set of possible homogenous, discrete states of a physical system. States of matter such as solid and liquid are examples of phases, as are different crystal lattice structures in metals such as iron. See also phase transition state of matter.
A measure of how far some cyclic behavior, such as wave motion, has proceeded through its cycle, measured in degrees or radians. At the beginning of the phase, its value is zero; at one quarter of its cycle, its phase is 90 degrees (π/2 radians); halfway through the cycle its value is 180 degrees (π radians), and so on.♦ The phase angle between two waves is a measure of their difference in phase. Two waves of the same frequency that are perfectly in phase have phase angle zero; if one wave is ahead of the other by a quarter cycle, its phase angle 90 degrees (π/2 radians); waves that are perfectly out of phase have phase angle 180 degrees (π radians), and so on. See more at wave.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.