1 B2 neutral
To introduce a new system, law, or practice gradually over a set period rather than all at once.
"The new safety regulations will be phased in over three years to give businesses time to adjust."
separable
phase in
B2 neutral separable transitive
To introduce or implement something new gradually, in stages, over a period of time.
In plain English
To start using something new slowly, a little at a time, so the change isn't too sudden.
What does "phase in" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 neutral
To gradually incorporate new employees, equipment, or resources into an existing operation.
"The school decided to phase in tablet computers one year group at a time."
separable
Usage tip
Commonly used in business, law, government, and education to describe the gradual adoption of new rules, systems, or technologies. Often appears in passive constructions: 'the new system will be phased in over two years'. The opposite of 'phase out'.
Words that pair with "phase in"
Natural word combinations native speakers use most often.
regulations system technology curriculum changes policy
How to conjugate "phase in"
The five tense forms you'll use most often.
Base
phase in
I/you/we/they
3rd person
phases in
he/she/it
Past simple
phased in
yesterday
Past participle
phased in
have + pp
-ing form
phasing in
continuous
Hear "phase in" in the wild
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Other ways to say "phase in"
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Keep exploring
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