What is the meaning of glowering?

verb

• Look at with a fixed gaze.
  • usage: "The girl glared at the man who tried to make a pass at her"
  • synonyms: glower, glare
• Look angry or sullen, wrinkle one's forehead, as if to signal disapproval.
  • synonyms: frown, glower, lour, lower

adjective

• Showing a brooding ill humor.
  • usage: "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"
  • synonyms: dark, dour, glum, moody, morose, saturnine, sour, sullen