Musty, stale.

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1579.  

          They soone myght be corrupted,
Or like not of the frowie fede,
  Or with the weedes be glutted.
Spenser, ‘Shepherd’s Calendar,’ July. (N.E.D.)    

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1856.  This ere butter ’s a leetle grain frowy.—Whitcher, ‘The Widow Bedott Papers,’ No. 7.

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1866.  Mrs. Dayton is a decent housekeeper, and so her bread be not sour, her butter not frowy, the food abundant, and the table-cloth and dishes clean, she troubles her head little with the niceties and refinements of the ménage.—Mrs. Stowe, ‘Little Foxes,’ p. 117. (N.E.D.)

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