\ ˈfāz How to pronounce phase (audio) \

Definition of phase

 (Entry 1 of 2)

1 : a particular appearance or state in a regularly recurring cycle of changes phases of the moon
2a : a distinguishable part in a course, development, or cycle the early phases of her career
b : an aspect or part (as of a problem) under consideration
3 : 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, oscillation, or variation has advanced from its standard position or assumed instant of starting
4 : a homogeneous, physically distinct, and mechanically separable portion of matter present in a nonhomogeneous physicochemical system
5 : an individual or subgroup distinguishably different in appearance or behavior from the norm of the group to which it belongs also : the distinguishing peculiarity
in phase
: in a synchronized or correlated manner
out of phase
: in an unsynchronized manner : not in correlation


phased; phasing

Definition of phase (Entry 2 of 2)

transitive verb

1 : to adjust so as to be in a synchronized condition
2 : to conduct or carry out by planned phases
3 : to introduce in stages usually used with in phase in new models

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Other Words from phase


phasic \ ˈfā-​zik How to pronounce phasic (audio) \ adjective

Synonyms for phase

Synonyms: Noun

angle, aspect, facet, hand, side

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Phase and Faze

Phase and faze are homophones (words pronounced alike but different in meaning, derivation, or spelling) that may easily be confused. Despite the similarity in pronunciation, these words bear little semantic resemblance to one another.

Although phase can function as a verb – it is found especially in combinations such as phase out, phase in, and phase into, meaning “to end, begin, etc. in phases” – the word is most commonly encountered as a noun, in which it typically carries a meaning related to steps in a process, cycles, or stages of development (as in “phases of the moon”).

Faze is generally used only as a verb, and means “to daunt or disconcert.” It often appears in negative expressions such as “it didn’t faze her a bit” or “nothing fazes him.”

Examples of phase in a Sentence


The project will be done in three phases. He's in the final phase of treatment now. The building project marks a new phase in the town's development. He has been throwing tantrums a lot, but the doctor says it's just a phase. a calendar based on the phases of the moon
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Recent Examples on the Web: Noun

The project is being done in two phases — the pool is being constructed first, and work on amenities such as locker rooms and concessions is expected to begin by the end of 2019. Lilly Nguyen, Daily Pilot, "Building projects keep Newport-Mesa busy as new school year draws near," 31 Aug. 2019 For Florida State, the disappointing start to the season can be looked at in two phases. Scooby Axson,, "Florida State's Promising Opener Turns Into a Nightmare in Loss to Boise State," 31 Aug. 2019 Development would be in phases _ with the first 16 houses built on an extension of Wilson Way, currently a dead-end off Cougar Drive, according to the proposal. Jesse Leavenworth,, "44-lot subdivision proposed on one of Manchester’s last large parcels," 30 Aug. 2019 Johnson said disaster recovery occurs over time in phases and is not a linear process. Danny Hermosillo, Houston Chronicle, "Children traumatized by Hurricane Harvey express their emotions through art," 29 Aug. 2019 Officials have repeatedly said the restrictions will be lifted in phases but have not provided a definitive timeline, leaving the entire region in confusion. Mukhtar Ahmad, CNN, "Under the curtain: Kashmir residents contend with pellet guns and restrictions," 28 Aug. 2019 The plan was to build the Consolidated Correctional Treatment Facility in phases, ultimately moving thousands of inmates with mental health needs there from the newer Twin Towers Correctional Facility nearby. Matt Stiles, Los Angeles Times, "‘No more jails,’ just mental health centers. Is that a realistic policy for L.A. County?," 26 Aug. 2019 Work on the China Garden is progressing in phases and may take a decade to complete, Husson said. Zekriah Chaudhry, Twin Cities, "Hmong Cultural Plaza at Phalen Regional Park gets early funding," 23 Aug. 2019 Construction started in 2017 and the homes were built in phases with the help of 7,400 volunteers who contributed more than 67,000 hours to the project, Barlow said. Paulina Pineda, azcentral, "Habitat for Humanity opens 18 townhomes in Tempe, plans up to 20 single-family homes," 17 Aug. 2019

Recent Examples on the Web: Verb

Policymakers should also enact a plan implemented on a gradual, phased-in basis that will substantially reduce long-term deficits and debt. William G. Gale For Cnn Business Perspectives, CNN, "Don't be fooled by low interest rates. America's ballooning deficits are more than our economy can handle," 28 Aug. 2019 To appease moderate lawmakers, House Democrats had amended the bill to phase in the $15 minimum wage over seven years instead of six. Alexia Fernández Campbell, Vox, "The $15 minimum wage bill has all but died in the Senate," 16 Aug. 2019 Budget experts have said the best way to control costs on these programs would be to phase in changes over time to avoid abrupt disruptions in benefits. Damian Paletta, Washington Post, "Trump tells aides to look for big spending cuts in second-term, seeding confusion about budget priorities," 19 July 2019 Worley said by phasing in the changes, CPS hopes to avoid these additional costs. Rachel Berry,, "Two Cincinnati high schools implementing later start times," 19 June 2019 The plan calls for phasing in the ban, which many residents, environmentalists and at least one city council member strongly opposed. Maggie Angst, The Mercury News, "Palo Alto becomes first Bay Area city to ban plastic produce bags. But is it enough?," 10 June 2019 Sovereign Properties is building the Dolce Twin Creeks phase two project on the west side of U.S. Highway 75 near McDermott Drive. Steve Brown, Dallas News, "Allen apartment project gets $55.5 million in funding to kick off construction," 16 Aug. 2019 One bill in Sacramento, which has passed the state Senate, would even require California to follow older federal environmental standards as state policy if Trump successfully phases them out. Paul Rogers, The Mercury News, "How California has blocked Trump’s environmental rollbacks," 27 July 2019 Some disability advocates oppose workshops, arguing they’re exploitative, but others worry phasing them out entirely will leave no work options at all for some people with disabilities. Nyssa Kruse, Indianapolis Star, "Changes coming for Hoosiers with disabilities after state advances task force recommendations," 5 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'phase.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of phase


1647, in the meaning defined at sense 1


1904, in the meaning defined at sense 1

History and Etymology for phase


New Latin phasis, from Greek, appearance of a star, phase of the moon, from phainein to show (middle voice, to appear) — more at fancy

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Statistics for phase

Last Updated

4 Sep 2019

Look-up Popularity

Time Traveler for phase

The first known use of phase was in 1647

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More Definitions for phase



English Language Learners Definition of phase

: a part or step in a process : one part in a series of related events or actions
: a short period of time during which a person behaves in a particular way or likes a particular thing
: the shape of the part of the moon that is visible at different times during a month


\ ˈfāz How to pronounce phase (audio) \

Kids Definition of phase

1 : a step or part in a series of events or actions : stage I have completed the first phase of my training.
2 : the way that the moon or a planet looks to the eye at any time in its series of changes with respect to how it shines The new moon and the full moon are two phases of the moon.


\ ˈfāz How to pronounce phase (audio) \

Medical Definition of phase

1 : a particular appearance or state in a regularly recurring cycle of changes
2 : a distinguishable part in a course, development, or cycle the early phases of a disease
3 : a point or stage in the period of a periodic motion or process (as a light wave or a vibration) in relation to an arbitrary reference or starting point in the period
4 : a homogeneous, physically distinct, and mechanically separable portion of matter present in a nonhomogeneous physicochemical system especially : one of the fundamental states of matter usually considered to include the solid, liquid, and gaseous forms
5 : an individual or subgroup distinguishably different in appearance or behavior from the norm of the group to which it belongs also : the distinguishing peculiarity

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More from Merriam-Webster on phase

Thesaurus: All synonyms and antonyms for phase

Spanish Central: Translation of phase

Nglish: Translation of phase for Spanish Speakers

Britannica English: Translation of phase for Arabic Speakers Encyclopedia article about phase

Comments on phase

What made you want to look up phase? Please tell us where you read or heard it (including the quote, if possible).


readily or continually undergoing change

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