Etymology Inherited from Northern Middle English pete (recorded in Latin text as peta), of uncertain origin; perhaps from a Celtic language such as an unattested Pictish or Brythonic source, in turn possibly from Proto-Brythonic *peθ (“portion, segment, piece”); if so, it would be a doublet of piece.
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Soil formed of dead but not fully decayed plants found in bog areas, often burned as fuel.
On the return journey the engine ran short of coal, and came to a stand near Penygroes through shortage of steam. Fortunately, there was some peat in a nearby field, which the enginemen dug and the directors helped to carry to the engine. Steam was soon raised and the story had a happy ending!1958 September 23, J. M. Dunn, “The Afonwen Line—1”, in Railway Magazine, pages 595-596:
Etymology Probably from Middle Dutch pete (“godmother or godfather”) (modern Dutch peet (“godparent, old woman, grandmother; godchild”)), related to dialectal German Pfette, Pfetter (“godfather; godchild”)), German Pate (“godfather, sponsor”), Patin (“godmother”). Or alternatively, related to pet (“a favourite”).
And let it not displease thee, good Bianca, / For I will love thee ne'er the less, my girl. / A pretty peat!c. 1590–1592 (date written), William Shakespeare, “The Taming of the Shrew”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act I, scene i], line 78: