glum (adj.)

• beetle-browed
• black
• brooding
• broody
• chapfallen
• crabbed
• crestfallen
• dark
• dejected
• depressed
• dismal
• dispirited
• doleful
• dour
• down
• frowning
• gloomy
• glowering
• grim
• long-faced
• low
• lowering
• lugubrious
• melancholy
• moody
• morose
• oppressed
• pessimistic
• sad
• saturnine
• scowling
• silent
• sour
• sulky
• sullen
• surly
• taciturn
• woebegone