Sc. [Cf. SUMPH sb.1] intr. To be stupid; now chiefly, to be sulky.

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a. 1689.  Cleland, Poems (1697), 113 (Jam.). They’re skant of wit, Who … Will sumph and vote they wot not what.

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1867.  Gregor, Banffsh. Gloss., Sumph, to show sour, sulky temper.

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1894.  Crockett, Lilac Sunbonnet, 73. Liein’ sumphin’ an’ sleepin’ i’ the middle o’ the forenicht.

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