Etymology From Middle English croupe, from Old French croupe (“rump, body”), from Old Norse kroppr (“body, trunk, mass”), from Proto-Germanic *kruppaz (“body, mass, heap, collection, crop”), from Proto-Indo-European *grewb- (“to curve, bend, crawl”). More at crupper, doublet of croupe, group, and crop.
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The top of the rump of a horse or other quadruped.
So light to the croup the fair lady he swung, / So light to the saddle before her he sprung.1808 February 22, Walter Scott, “(please specify the introduction or canto number, or chapter name)”, in Marmion; a Tale of Flodden Field, Edinburgh: […] J[ames] Ballantyne and Co. for Archibald Constable and Company, […]; London: William Miller, and John Murray, →OCLC:
The guib [a kind of antelope] is of the mean dimensions, or four feet and a half in total length, and two and a half high at the shoulders, but rather higher at the croup.1835, Charles Frederick Partington, The British cyclopædia of natural history:
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Curved like a stallion's croup, from dusk to dawn, / And drums upon it with his heels, whereby / Is bred the neighing thunder in the hills.1892, Rudyard Kipling, “The Sacrifice of Er-Heb”, in Barrack-Room Ballads and Other Verses, 3rd edition, London: Methuen & Co. […], →OCLC, page 146:
Etymology From Scots croup, croop (“the croup”), from Scots croup, crowp, croop (“to croak, speak hoarsely, murmur, complain”), from Old Scots crowp, crope, croap (“to call loudly, croak”), alteration of rowp, roup, roip, rope (“to cry, cry hoarsely, roop”), from Middle English roupen, ropen, from Old English hrōpan (“to shout, proclaim; cry out, scream, howl”), from Proto-Germanic *hrōpaną (“to shout”), from Proto-Indo-European *ker-, *kor- (“to caw, crow”). More at roop. In the medical sense introduced by Edinburgh physician Francis Home.
Etymology From Scots croup, croop (“the croup”), from Scots croup, crowp, croop (“to croak, speak hoarsely, murmur, complain”), from Old Scots crowp, crope, croap (“to call loudly, croak”), alteration of rowp, roup, roip, rope (“to cry, cry hoarsely, roop”), from Middle English roupen, ropen, from Old English hrōpan (“to shout, proclaim; cry out, scream, howl”), from Proto-Germanic *hrōpaną (“to shout”), from Proto-Indo-European *ker-, *kor- (“to caw, crow”). More at roop. In the medical sense introduced by Edinburgh physician Francis Home.
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Medicine, Pathology, Sciences An infectious illness of the larynx, especially in young children, causing respiratory difficulty.
Yes; I've nursed five children and buried three; and the one I loved the best of all, and tended through croup, and teething, and measles, and hooping-cough, and brought up with foreign masters, regardless of expense, […].1847 January – 1848 July, William Makepeace Thackeray, Vanity Fair […], London: Bradbury and Evans […], published 1848, →OCLC:
Percy Northumberland Driscoll[…]had had children around his hearthstone; but they were attacked in detail by measles, croup and scarlet fever, and this had given the doctor a chance with his effective antediluvian methods; so the cradles were empty.1897, Mark Twain [pseudonym; Samuel Langhorne Clemens], “[Pudd’nhead Wilson] Chapter”, in The Tragedy of Pudd’nhead Wilson: And the Comedy Those Extraordinary Twins, Hartford, Conn.: American Publishing Company, →OCLC, page 22: