Phaseout is likely misspelled.
Phaseout has no English definition.
As a noun fadeout is
a gradual disappearance.
phaseout
English
Noun
The action of phasing out; an incremental removal or reduction. fadeout
English
Noun
(
en noun)
A gradual disappearance.
*{{quote-news, year=2009, date=February 17, author=Howard W. French, title=Surviving a Hitch in an Army of Boys, work=New York Times citation
, passage=The scene ends with a
fadeout to unconsciousness.}}