cheerless
colorless
colourless
depressing
uncheerful
black
bleak
dark
darkling
darksome
depressed
dim
dingy
dire
dismal
doleful
dolorous
dreary
dull
dusky
foreboding
funereal
gloomy
grave
grey
grim
grim-faced
grim-visaged
joyless
leaden
lowering
lugubrious
melancholic
melancholy
morbid
morose
mournful
murky
overcast
sad
sedate
serious
shadowy
sober
solemn
staid
subfusc
unhappy
awful
lonely
majestic
ominous
somber
sullen