phase out

phase out — phrasal verb

  • phase outbase form
  • phases out3rd person singular
  • phasing out-ing form
  • phased outpast simple

1. to stop using, producing, or supplying something gradually and deliberately, usu

1.phrasal verbtransitiveB2
Definition

to stop using, producing, or supplying something gradually and deliberately, usually because it is being replaced with something newer or better.

Example

Constanza's team is phasing out the old database system this quarter.

phase out + object (old system)

Single-use plastic bags are being phased out across Taiwan.

passive: be phased out

Common collocations
  • phase out subsidies
  • phase out a product line
  • phase out an old system
  • gradually phase out
  • completely phase out
  • planned phase-out
Synonyms
  • discontinue

    more general; can be sudden or gradual, while phase out specifically implies a gradual, planned withdrawal

  • eliminate

    stronger and more final; does not carry the sense of a staged, gradual process

  • retire

    used for equipment or assets; less common for policies or practices

Antonyms
  • phase in

    the direct opposite — to introduce something gradually as something else is removed

  • introduce

    general opposite, but does not imply gradualness

Grammar Patterns

phase + object + out

phase out + object

be phased out

Usage Note

Frequently used in the passive (be phased out) when the focus is on the item being removed rather than the person doing it. The opposite process is phase in.

Common Mistakes

The company phased out the project overnight.
The company cancelled the project overnight.
phase out describes a gradual process, not a sudden stop.
We need to phase out the use of this chemical soonly.
We need to phase out the use of this chemical soon.
'soonly' is not a word; use 'soon'.

Etymology

GreekEnglish

The verb phrase 'phase out' comes from the noun 'phase', meaning a stage or step in a process, combined with the adverb 'out' to convey the idea of moving something out of use step by step. The expression became common in the mid-20th century, particularly in business, industry, and government contexts where changes were planned in stages.