What is pl. Etym: [Short for blue devils.] Low spirits; a fit of despondency; melancholy. [Colloq.] Berlin blue, Prussian blue. -- Mineral blue. See under Mineral. -- Prussian blue. See under Prussian called?

blue — pl. Etym: [Short for blue devils.] Low spirits; a fit of despondency; melancholy. [Colloq.] Berlin blue, Prussian blue. -- Mineral blue. See under Mineral. -- Prussian blue. See under Prussian. (Webster's 1913.)

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