i Register
In some senses, glum is marked as obsolete. Watch for register when choosing this word.
adj
Despondent; moody; sullen.
I[…]frighten people by my glum face.
[…] and the prospect of three more days of teaching before the weekend break, Mr. MacPherson felt unusually glum.
verb
To look sullen; to be of a sour countenance; to be glum.
upon me he gan to loure and glum, Enforcing him so for to ryse withall, But that I shortly unto hem did cum, With his thre hedes he spytte all his venum
noun
sullenness
That they be deaf and dumb, And play silence and glum