Source : Webster's Revised Unabridged Dictionary (1913)

Glower \Glow"er\, v. i. [imp. & p. p. {Glowered}; p. pr. & vb.
   n. {Glowering}.] [Cf. {Gloar}.]
   to look intently; to stare angrily or with a scowl.
   --Thackeray.

Source : WordNet®

glowering
     adj : showing a brooding ill humor; "a dark scowl"; "the
           proverbially dour New England Puritan"; "a glum,
           hopeless shrug"; "he sat in moody silence"; "a morose
           and unsociable manner"; "a saturnine, almost
           misanthropic young genius"- Bruce Bliven; "a sour
           temper"; "a sullen crowd" [syn: {dark}, {dour}, {glum},
            {moody}, {morose}, {saturnine}, {sour}, {sullen}]