A
fallen angel is a wicked or rebellious
angel that has been cast out of
heaven. The term "fallen angel" does not appear in the
Bible, but it is used of angels who
sinned (such as those referred to in , "For if God did not spare angels when they sinned, but cast them into hell and committed them to chains of gloomy darkness to be kept until the judgment ..."), of angels cast down to the earth in the
War in Heaven, of
Satan,
demons, or of certain
Watchers. The term has become popular in fictional literature regarding angels.