The noun is derived from Middle English spate, spait (“a flood”), influenced by Scots spate (“torrent of water, flood; heavy downpour of rain; (figurative) bout of drinking; large crowd of people; flood of events, words, etc.”). The further etymology of the Middle English and Scots words is uncertain; they are possibly related to English spatter and Dutch spatten (“to spatter, splash”), possibly ultimately from Proto-Indo-European *sp(y)ēw-, *spyū- (whence English spit (“to evacuate (saliva or another substance) from the mouth, etc.”)), which is imitative of spitting. The verb is derived from the noun, probably influenced by Scots spate (“to flood, swell; to rain heavily; (figurative) to scold fiercely”).
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Scotland A (sudden) flood or inundation of water; specifically, a flood in or overflow of a river or other watercourse due to heavy rain or melting snow; (uncountable, archaic) flooding, inundation.
Thys Lepidium that Pliny & Paul [of Aegina] deſcribe⸝ groweth plentuouſly about the water ſyde that rynneth thorow Morpeth in Northumberland⸝ in ſuche places as great heapes of ſtones are caſten together wyth the myght of a great ſpat or flood.1562, Wylliam Turner [i.e., William Turner], “Of the Herbe Called Lepidium or Dittani”, in The Second Parte of Guilliam Turners Herball⸝ […], Cologne: […] Arnold Birckman, →OCLC, folio 35, recto:
Arous'd by bluſtering vvinds an' ſpotting thovves, / In mony a torrent dovvn the ſnavv-broo rovves; / VVhile craſhing ice, borne on the roaring ſpeat, / Svveeps dams, an' mills, an' brigs, a' to the gate; […][1787, Robert Burns, “Auld Brig”, in Poems, Chiefly in the Scottish Dialect. […], 2nd edition, volume I, Edinburgh: […] T[homas] Cadell, […], and William Creech, […], published 1793, →OCLC, page 76:
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The last tall son of Lot and Bellicent, / And tallest, Gareth, in a showerful spring / Stared at the spate. A slender-shafted Pine / Lost footing, fell, and so was whirled away.1874, Alfred Tennyson, “Gareth and Lynette”, in Idylls of the King (The Works of Alfred Tennyson; V), cabinet edition, London: Henry S. King & Co., […], →OCLC, page 37:
Scamander was indeed a great power for the Trojans; it was the great river of the country, […] His floods, however useful in time of war, would in time of peace do fearful damage. […] [H]e carried away, in sudden spates, many of the horses that were pastured on his banks.1858, W[illiam] E[wart] Gladstone, Studies on Homer and the Homeric Age. […], volume III, Oxford, Oxfordshire: University Press, →OCLC, part II (Ilios. The Trojans Compared and Contrasted with the Greeks.), page 158:
It [the Halladale river] receives the whole of its water-supply from a number of hill burns and several lochs of inconsiderable extent. it follows, therefore, that after rain the surplus water soon runs out, and the river soon dwindles down to an almost unfishable condition. […] An ordinary spate will not suffice to keep the river in good order for more than a couple of days.1886 February 20, W. Murdoch, “Salmon and Trout-fishing in the Highlands of Scotland.—VII. The Halladale (Sutherlandshire).”, in R. B. Marston, editor, The Fishing Gazette; Devoted to Angling, River, Lake, and Sea Fishing and Fish Culture, volume XII, London: Charles William Bradley & Co. […], →OCLC, page 97, column 1:
At Odendaal, where he [Christiaan de Wet] had hoped to cross, the river was in spate, the British flag waved from a post upon the further side, and a strong force of expectant Guardsmen eagerly awaited him there.1902, Arthur Conan Doyle, “The Campaign of De Wet”, in The Great Boer War […], revised (American) edition, New York, N.Y.: McClure Phillips & Company, →OCLC, page 309:
Doun comes a jaw o' droukin' rain / Upon their honours— / God sends a spate outower the plain, / Or mebbe thun'ers.[1887, Robert Louis Stevenson, “The Blast—1875”, in Underwoods (in Scots), London: Chatto and Windus, […], →OCLC, book II (In Scots), page 101:
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Scotland, Figuratively A sudden increase or rush of something; a flood, an outburst, an outpouring.
Thy rural loves are nature's ſel; / Nae bombaſt ſpates o' nonſenſe ſwell; / Nae ſnap conceits, but that ſweet ſpell / O' witchin love, […]1869, Robert Burns, “Poem on Pastoral Poetry”, in Poems, Chiefly in the Scottish Dialect, volume III (Posthumous Poems), Kilmarnock, Scotland: […] James M‘Kie, →OCLC, page 45:
Here is a fine spate of work—a day diddled away, and nothing to show for it!1826 September 6 (date written), Walter Scott, “[Entry dated 6 September 1826]”, in David Douglas, editor, The Journal of Sir Walter Scott […], volume I, Edinburgh: David Douglas, published 1890, →OCLC, page 250:
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He couldnae weel tell how—maybe it was the cauld to his feet—but it cam' in upon him wi' a spate that there was some connection between thir twa, an' that either or baith o' them were bogles.[1881 October, Robert Louis Stevenson, “Thrawn Janet”, in The Merry Men and Other Tales and Fables, 1st American (authorized) edition, New York, N.Y.: Charles Scribner’s Sons, published 1887, →OCLC, page 156:
But, my dear David, this world is a censorious place—as who should know it better than myself, who have lived ever since the days of my late departed father, God sain him! in a perfect spate of calumnies?1892, Robert Louis Stevenson, “A Twosome”, in Catriona, London; Edinburgh: Thomas Nelson & Sons, →OCLC, page 331:
Only let your language match your subject, then it will be shapely and free; but take care all the time not to overwhelm your work in a spate of words to attain the fluency of Isaeus; and that it slip not out too freely, avoid the danger of Strada [Zanobi da Strada?].1928, Thomas Browne, “To a Friend Intending a Difficult Work”, in W[illiam] R[chard] LeFanu, transl., edited by Geoffrey Keynes, The Works of Sir Thomas Browne, new edition, volume III, London: Faber & Faber, published 1964, →OCLC, page 155:
The spate of similar cases filed and decided by lower courts since our decision in Baker [v. Carr] amply shows that the problem of state legislative malapportionment is one that is perceived to exist in a large number of the States.1964 June 15, Earl Warren, Chief Justice, Supreme Court of the United States (delivering the court’s opinion), “Reynolds, Judge, et al. v. Sims, et al.”, in Henry Putzel, jr., reporter, United States Reports: Cases Adjudged in the Supreme Court at October Term, 1963 […], volume 377, Washington, D.C.: United States Government Printing Office, →ISSN, →OCLC, section II, page 556:
The noun is derived from Middle English spate, spait (“a flood”), influenced by Scots spate (“torrent of water, flood; heavy downpour of rain; (figurative) bout of drinking; large crowd of people; flood of events, words, etc.”). The further etymology of the Middle English and Scots words is uncertain; they are possibly related to English spatter and Dutch spatten (“to spatter, splash”), possibly ultimately from Proto-Indo-European *sp(y)ēw-, *spyū- (whence English spit (“to evacuate (saliva or another substance) from the mouth, etc.”)), which is imitative of spitting. The verb is derived from the noun, probably influenced by Scots spate (“to flood, swell; to rain heavily; (figurative) to scold fiercely”).
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Scotland, Archaic To (suddenly) flood or inundate (a river or other watercourse) with water.
[H]e paused in a reverie of wilderment and wonder when he could not discern the old fishing-places—they were deeply and darkly flooded for many yards on every side of the spated stream.1844 October, J. Nevay, “Mary Hepburn; or, The Victim of Slander. Chapter X.”, in The Ladies’ Cabinet of Fashion, Music, and Romance, volume II (New Series), London: G. Henderson, →OCLC, page 255:
A few of the very best angling streams in the Highlands are almost perennial in their flow; the Halladale, on the contrary, is subject to spating.1886 February 20, W. Murdoch, “Salmon and Trout-fishing in the Highlands of Scotland.—VII. The Halladale (Sutherlandshire).”, in R. B. Marston, editor, The Fishing Gazette; Devoted to Angling, River, Lake, and Sea Fishing and Fish Culture, volume XII, London: Charles William Bradley & Co. […], →OCLC, page 97, column 1:
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The gates of Anger open, and the flood, / Spated with hate, unstemmed of men, pours out, / Drenching the trench with hot and beaded blood, / Choking each challenging or anguish'd shout.1918, Robert B. Ross, “The Silent Guns”, in The Fifty-first in France, London; New York, N.Y.: Hodder and Stoughton, →OCLC, part I (From May to December 1915), page 84:
The day was lovely and clear after the rain. The river had not spated as much as I had expected, and there was only one place in my sector where lorries might have found difficulty in crossing the nala.[1938], Rajput [pseudonym; Arthur John Eardley Dawson], chapter 12, in Khyber Calling!, London: Hurst & Blackett, →OCLC, section 3, page 181:
river strontian, argyll […] This is a good example of a short, west-coast spating oligotrophic river. […] The river is subject to a rise in water level of up to 1 m following heavy rain and the water is clear and fairly low in dissolved nutrients.1977, “Open Waters”, in A Nature Conservation Review, volume 2 (Site Accounts), Cambridge, Cambridgeshire: Cambridge University Press for the Nature Conservancy Council and Natural Environment Research Council, published 2011, →ISBN, page 202, column 1:
On one occasion the Segre was spating after heavy rain and threatening to overflow, whereupon [Saint] Ermengol fell down on his knees "begging Christ that the force of the river might turn away from the Virgin Mother" and crying out, "O water, do you dare to perform this sacrilege so that you might break up the estate of the church because you are bored with your usual path? Desist from this crime, violator, I challenge you in the divine name to hear my prayer." The next day the waters subsided, and Ermengol was able to continue the construction of a bridge across the Segre.2018, Matthew Carr, “Scholars, Pilgrims, and Troubadours”, in The Savage Frontier: The Pyrenees in History and the Imagination, New York, N.Y.: The New Press, →ISBN, part II (Pyrenean Crossings):