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• phase-in
  phase-in

  noun

  an act or instance of phasing in; gradual introduction or implementation.
• phase in
  phase in

  verb

  (tr, adverb) to introduce in a gradual or cautious manner

phase-in

American  

[fayz-in] / ˈfeɪzˌɪn /

noun

1. an act or instance of phasing in; gradual introduction or implementation.

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phase in British  

verb

1. (tr, adverb) to introduce in a gradual or cautious manner

   the legislation will be phased in over two years

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phase in Idioms  

1. Introduce one stage at a time. For example, New technology must be phased in or the office will be overwhelmed. The antonym is phase out, meaning “to bring or come to an end, one stage at a time,” as in The department is phasing out all the older computers. [Mid-1900s]

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Etymology

Origin of phase-in

Noun use of verb phrase phase in

Example Sentences

See Examples For:

phase-in phase in

More than a dozen other states have built robust, sustainable school-choice programs on the same foundation: clear rules, sensible phase-in, fund preapprovals, and resources dedicated to core academic expenses.

From The Wall Street Journal ● Jul. 12, 2026

In contrast, the County Council proposes just a two-year phase-in for most businesses and does not factor in tips and benefits.

From Seattle Times ● May 13, 2024

FDA proposes a phase-in of the new rules over 4 years, but its specific demands aren’t yet clear.

From Science Magazine ● Dec. 12, 2023

But that was before the legislation was narrowed down to include a years-long phase-in plan.

From Los Angeles Times ● Oct. 13, 2023

Important commodities - such as sugar, rice and bananas - are virtually excluded by long phase-in periods.

From The Belgian Curtain Europe after Communism by Samuel Vaknin

When the discount carrier started in 2008, it marked a second phase in Dubai’s rise to become one of the dominant forces in global aviation.

From The Wall Street Journal ● Oct. 7, 2026

Google said the construction phase in 2027 and 2028 would support more than 37,000 jobs and contribute an average of €3.6bn a year to Finland's economy.

From BBC ● Oct. 6, 2026

Instead, the researchers say the Arctic may have entered a different phase in which yearly atmospheric conditions have a stronger influence over how long the melt season lasts.

From Science Daily ● Sep. 23, 2026

Over the next few years, Jay Leno’s Law will phase in smog check exemptions for collector cars built from model years 1976 through 1985 that are not used as a primary mode of transportation.

From Los Angeles Times ● Sep. 17, 2026

That fall Ruth had to fly back to Florida to sell her condo, pack her belongings, and wrap things up in general to prepare for this new phase in her life.

From "The Miseducation of Cameron Post" by emily m. danforth