To be in the dumps. Out of spirits; in the “sullens.” According to etymological fable, it is derived from Dumops, King of Egypt, who built a pyramid and died of melancholy. Gay's Third Pastoral is Wednesday, or the Dumps. (German, dumm, stupid, dull.)
“Why, how now, daughter Katharine? in your dumps?” —Shakespeare: Taming of the Shrew, ii. 1.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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