expression

phase out

to discontinue gradually

In Phrasal Verbs

In more detail

1. (verb) to gradually stop using or discontinue something over a period of time

2. (verb) to introduce something gradually in stages

Examples

1. The company will phase out the old software by next year.
2. The new system will be phased out over the next few months.

How to use phase out

Phase out describes a deliberate, gradual discontinuation or introduction of something over a defined period, often used in business, environmental, or organizational contexts. It emphasizes the staged nature of the process rather than abrupt change. When used transitively with meaning 2, the related phrasal verb is 'phase in' (introduce new elements while phasing out old ones).

Common phrases

phase out a product
phase out gradually
phase out over time
phase out coal
phase something out completely

Synonyms

discontinue gradually · eliminate gradually · wind down · phase in (for meaning 2) · introduce gradually

Word family

phase in · phasing out · phased out

A common mistake

Learners sometimes confuse 'phase out' with 'fade out,' though 'phase out' is more formal and suggests a planned, managed process, while 'fade out' suggests a more natural or uncontrolled decline.

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