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Webster 1913 Edition
Glum
Glum
,Adj.
 Moody; silent; sullen. 
I frighten people by my 
 glun 
face. Thackeray.
Glum
,Verb.
 I.
 To look sullen; to be of a sour countenance; to be glum. 
[Obs.] 
Hawes.
 Webster 1828 Edition
Glum
GLUM
,Adj.
  GLUM
,Noun.