In a mournful manner; as if in mourning for something.(adverb)
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Use "mournfully" in a sentence
"Pine needles falling on an empty lawn chair, as you watch mournfully from the window. veggieburger"
"The thing that is common to all these people, whether it is Pétain mournfully preaching the discipline of defeat, or Sorel denouncing liberalism, or Berdyaev shaking his head over the Russian Revolution, or Beachcomber delivering side-kicks at Beveridge in the Express, or Huxley advocating non-resistance behind the guns of the American Fleet, is their refusal to believe that human society can be fundamentally improved."
"As he spoke, he jingled the coins mournfully in his palm, and gazing upon them with a parental air, exclaimed, --"