en passant

1. not comparableboard gamesOf a capture, performed by a pawn on an enemy pawn that has just passed over its attack zone.

1. not comparableIn passing, by the way, incidentally.First known use early 17th c.

   Mr. William Poole called in, and examined […] I spoke to sheriff Thorpe, en passant, one day in Sackville-street, saying, "I should wish to be on the next commission jury;" and he said, it should be so.

   1823 May 6, “Sheriff of Dublin—Inquiry into His Conduct”, in T[homas] C[urson] Hansard, editor, The Parliamentary Debates: Forming a Continuation of the Work Entitled “The Parliamentary History of England from the Earliest Period to the Year 1803.” (New Series; Commencing with the Accession of George IV), volume IX (Comprising the Period from the First Day of May, to the Nineteenth Day of July, 1823), London: Printed by T. C. Hansard at the Pater-noster-Row Press; for Baldwin, Cradock, and Joy [et al.], published 1824, →OCLC, columns 71–72

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   Turtle doves have long been celebrated for their fidelity; and this turtle dove, though he flirts, en paſſant, with a ſky-lark, a jay, and a quail, does not materially diſcredit the famed conſtancy of his ſpecies, theſe birds being all coquettes: but when he meets (as he fortunately does) with an amiable dove-mate, he is as faithful as any turtle, of any grove.

   1791 January, “[Miscellaneous.] Art. 65. The Turtle Dove. A Tale, from the French of M. de Florian. 8vo. pp. 25. 1s. Printed at Caen in Normandy; and Sold in London by Payne [book review]”, in The Monthly Review; or, Literary Journal, Enlarged, volume IV, London: Printed for R[alph] Griffiths; and sold by T[homas] Becket, in Pall Mall, →OCLC, page 113

   [H]e [the newly elected Pope] is placed on the altar, where all the cardinals, according to their rank, pay their reverence to him, and kiss his feet, hands, and mouth. I should observe, en passant, that cardinals only have the right to kiss the Pope's hand.

   1825, [Victor-Joseph Étienne] de Jouy, “The Conclave”, in The Hermit in Italy, or Observations on the Manners and Customs of Italy; being a Continuation of the Sketches of French Manners, … In Three Volumes, volume I, London: Printed for Geo[rge] B[yrom] Whittaker, Ave-Maria Lane, →OCLC, pages 170–171

   We merely suggest, en passant, that some of our best citizens might deem it a wonderful and beauteous thing if, in addition to paying the fine, Mr. Louden could serve for the loyal Happy his six months in the Bastile!

   1905 October, Booth Tarkington, “‘Outer Darkness’”, in The Conquest of Canaan: A Novel, New York, N.Y.; London: Harper & Brothers Publishers, →OCLC, page 128

2. not comparableboard gamesOf a capture of an enemy pawn, by moving one's pawn to the square that the enemy pawn has just passed over.

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   [I]f the opponent chooses to make this capture, he must do it immediately on his next move – if he makes any other move on his next move, he forever loses the chance to capture that pawn en passant, though he still retains the right to capture another pawn en passant should a similar situation arise elsewhere.

   2007, Mark A. Borders, “The Rules”, in The Self-Improvement of Chess: Why the Game's Basics Apply to Daily Living, [Raleigh, N.C.]: Lulu, →ISBN, page 12

plural en passants

1. board gamesA move in which a pawn captures an opposing pawn on the same rank immediately after the latter has moved forward two squares on its first move in the game, as if it had moved forward only one square.

   Spectators are privy to awe inspiring castles, baffling forks, and breathtaking en passants.

   1998 December 11, Glenn Kaplan, “Chess: not just for losers, but also Trekkies”, in The Oberlin Review, volume 127, number 12, Oberlin, Oh.: The Union Library Association, →ISSN, →OCLC, archived from the original on 22 Jan 2017

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   En passant is the rarest of moves. It is a French phrase that means "in passing." This occurs when one player moves a pawn two spaces forward, on its first move, to try to avoid a capture by an opponent pawn. When this happens, the opponent may move his pawn diagonally to the square that the first player passed over (i.e., as if he only moved one space forward). The pawn from the first player is then considered captured and removed from the board.

   2007, Mark A. Borders, “The Rules”, in The Self-Improvement of Chess: Why the Game's Basics Apply to Daily Living, [Raleigh, N.C.]: Lulu, →ISBN, page 12

   Before he returns to performing some castles and en passants, [Kendall] Williams has to determine his endgame in the tourney.

   2012 March 17, Ben Watanabe, “New Mexico Point Guard Kendall Williams Puts Chess Match on Hold During Tournament”, in New England Sports Network, archived from the original on 05 Mar 2016

   Grande Prairie's Sandman Hotel will be the scene of some castling, en passants and checkmate action this weekend when the 29th Trumpeter Classic Chess Tournament gets underway.

   2012 May 31, Greg Amos, “Trumpeter Classic chess tournament begins today”, in Grande Prairie Daily Herald-Tribune, Grande Prairie, Alta.: Sun Media, →ISSN, →OCLC