by-blow

plural by-blows · alternative byblow · alternative bye-blow

1. A blow struck to the side or from the side, as in swordplay; a secondary or incidental strike of any sort.

   As a by-blow in the course of his relentless campaigns against Louis, Willem gained the three thrones of Britain in 1699 – but what a by-blow this proved!

   2009, Diarmaid MacCulloch, A History of Christianity, Penguin, published 2010, page 732

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   Either commander took speedy advantage of it—Hopton to make a swift diversion into Sussex and capture Arundel Castle (which was but a by-blow, for in a few weeks he had lost it again).

   1910, Arthur Quiller-Couch, “The Copernican Convoy,”, in Corporal Sam and Other Stories

2. slangAn illegitimate child; a child of an unknown or unmarried father.

   c. 1892, Herman Melville, "Billy Budd, Foretopman" (novella), in Herman Melville: Selected Tales and Poems, Holt, Rinehart & Winston (1950), p. 298, Yes, Billy was a foundling, a presumable bye-blow, and, evidently, no ignoble one.

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   ‘Nay,’ said the landlady, ‘if I thought he was a gentleman's son, thof he was a bye-blow, I should behave to him in another guess manner; for many of these bye-blows come to be great men, and, as my poor first husband used to say, never affront any customer that's a gentleman.’

   1749, Henry Fielding, Tom Jones, Folio Society, published 1973, page 275

   The best hope has been that friends and family would talk, a hope partly realized in this discreet but perceptive memoir by his illegitimate daughter. . . . Little Mary was a by-blow and an inconvenience.

   1971 August 2, Brad Darrach, “Knee-High to Ezra Pound”, in Time

   Synonyms: bastard