Definition of "disgruntled"

About John Marin, there move sad, disgruntled beings, full of talk and lamentations. [...] They bewail the fact that in America, soil is poor and unconducive to growth, and men remain unmoved by growing green. But Marin persists, and what ebullience and good humour, in the rocky ungentle loam?

1922 April, Paul Rosenfeld, “The Water-Colours of John Marin: A Note on the Work of the First American Painter of the Day”, in John Peale Bishop, editor, Vanity Fair, volume 18, number 2, New York, N.Y.: Vanity Fair Publishing Company, page 48, column 2

A good proportion of British Railways' most disgruntled main line passengers will be found among those who have to make long-distance journeys at week-ends, when trains are apt to be diverted and re-timed because of large-scale engineering works.

1960 June, “Talking of Trains: Week-end diversions”, in Trains Illustrated, page 323