Definition of "embrasure"

But there were less casualties than might have been expected, and the barricade rose steadily, a wall of concrete two feet thick, with embrasures for two machine-guns and a small field gun.

1938 April, George Orwell [pseudonym; Eric Arthur Blair], chapter VI, in Homage to Catalonia, London: Secker & Warburg

She had a special seat there, a little embrasure between two upright slabs of sandstone, which was sheltered and private.

1938, Norman Lindsay, Age of Consent, 1st Australian edition, Sydney, N.S.W.: Ure Smith, published 1962, page 128

When the fit had spent itself he walked weakly to the window and, lifting the sash, sat in a corner of the embrasure and leaned his elbow upon the sill.

1916, James Joyce, chapter 3, in A Portrait of the Artist as a Young Man‎

Now he stands in a window embrasure, Liz's prayer book in hand.

2009, Hilary Mantel, Wolf Hall, Fourth Estate, published 2010, page 155

And suddenly; where injury of chance / Puts back leave-taking, justles roughly by / All time of pause, rudely beguiles our lips / Of all rejoindure, forcibly prevents / Our lock'd embrasures, strangles our dear vows / Even in the birth of our own labouring breath:

c. 1602, William Shakespeare, “The Tragedie of Troylus and Cressida”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act IV, scene iv]