phase down

phase down (third-person singular simple present phases down, present participle phasing down, simple past and past participle phased down)

1. (transitive) To gradually reduce the size or scale of
   • 2021 November 13, Sharma, Alok, “Alok Sharma’s remarks at the COP26 Closing Plenary”, in 2021 United Nations Climate Change Conference, Government of the United Kingdom, retrieved 2021-11-13:

     We have also, for the first time, adopted text to scale up clean power and phase down dirty coal.

• scale down
• scale up