“Glum” the adjective – to look sullen and frowning if referring a person, or to look gloomy, dark, and dismal if a thing – is apparently related to the verbs “glum” and “gloom”.  Now, I had thought that “glum” was an affect – a feeling.  Nope.  It’s an appearance, something we can see.  Related to a Low German word meaning “muddy”.

Very well, “glum” the obsolete yet occasionally dialectical verb means to look sullen.  To show a frown or scowl.  Nothing about underlying causes.  Etymologically, it also comes from the verb “gloom”.

To “gloom” is to look sullen, dismal dejected – the weather can gloom as well as persons by looking dark.  Also one can gloom something by making it dark or melancholy (but isn’t melancholy on the inside, not an appearance?)

Etymologically, our word comes through Middle German words for muddiness, fraudlent conduct(how interesting), and fogginess.  OED is quite clear that it’s a different root from “gloaming” and other twilight-related words.

• 02.036 There they all sat glum
• 07.142 and don’t look so glum.
• 11.020 and glummer
• 11.020 and glummer they became.
• 13.059 said Bilbo glumly.

“gloom, v.1.” OED Online. Oxford University Press, June 2015. Web. 26 July 2015.

“glum, adj.” OED Online. Oxford University Press, June 2015. Web. 26 July 2015.

“glum, v.” OED Online. Oxford University Press, June 2015. Web. 26 July 2015.