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weak; weakly; feeble; frail; delicate; faint (voice, sunlight, etc.)
弱々しい声で助けを求めた。
They asked for help in a feeble voice.
病気の後、彼の足取りは弱々しかった。
After the illness, his steps were feeble.
弱々しく揺れる炎を見つめていた。
I gazed at the faintly flickering flame.