Answer: dreary

AnswerCrossword Clue
DREARY'Once upon a midnight -- . . .'
DREARYLike a cloudy day
DREARYDrab
DREARYLackluster
DREARYDepressing
DREARYNot bright
DREARYGray
DREARYLike the Dry Era, to drinkers
DREARYOvercast
DREARYLike rainy weather, say
DREARYLike Poe's "midnight"
DREARYDepressingly dismal
DREARY"Once upon a midnight ........"
DREARYLike rainy days, to some
DREARYBleak
DREARY"Once upon a midnight ... ..."
drearya dismal person / dismal (gloomy (dismally dark))
drearygloomy; sad
drearyboring
DREARYSad.
DREARYTedious
DREARYLike a rainy day
DREARYDepressive
DREARYLike a dismal day
DREARYLacking in liveliness
DREARYHumdrum
DREARYGloomy
DREARYDismal
DREARYNot all that bright
DREARYCheerless
DREARYMonotonous.
DREARYDismal.
DREARYGloomy.
DREARYCheerless.
DREARYBleak.
DREARYDoleful.
DREARY"Once upon a midnight ..."
DREARYFifth word of "The Raven"