From Late Middle Englishdefilen(“to make dirty, befoul; to contaminate (the body or an organ) with dirt or disease; to pollute morally or spiritually; to desecrate, profane; to violate (the sanctity of marriage, an agreement or oath, etc.); to rape; to slander; to abuse; to destroy; to injure; to treat unfairly, oppress”)[and other forms],[1] a variant of defoulen(“to make dirty, defile, pollute; to contaminate (the body or an organ) with dirt or disease; to pollute morally or spiritually; to desecrate, profane; to violate (the sanctity of marriage, an agreement or oath, etc.); to have sexual intercourse with; to rape; etc.”)[2] (compare also defoilen).[3]Defoulen is derived from Old Frenchdefouler(“to trample; to oppress; to outrage; to pollute; to violate”), from de-(prefix indicating actions are done more strongly or vigorously) + fouler(“to trample, tread on; to mistreat, oppress”), foler(“to destroy; to mistreat”) (from Vulgar Latinfullare(“to full (make cloth denser and firmer by soaking, beating, and pressing)”), from Latinfullō(“person who fulls cloth, fuller”); further etymology uncertain, possibly from Proto-Indo-European*bʰleh₃-(“to blow; to inflate, swell; to bloom, flower”) or Etruscan𐌘𐌖𐌋𐌖(φulu)).[4] The English word is analysable as de-(intensifying prefix) +file(“(archaic) to corrupt; to defile”).
The Middle English word defilen was probably formed from defoulen on the analogy[4] of befilen(“to make dirty, befoul; to corrupt; to violate one's chastity; to desecrate; to slander”)[5] and befoulen(“to make dirty, befoul; to violate one's chastity; to vilify”),[6] respectively from filen(“to make foul, impure, or unclean, pollute; to pollute morally or spiritually; to desecrate, profane; to have sexual intercourse with; to rape; etc.”)[7] and foulen(“to make dirty, pollute; to become dirty; to defecate; to deface or deform; to pollute morally or spiritually; to damage, injure; to destroy; to treat unfairly, oppress; to tread on, trample”).[8]Filen and foulen are respectively from Old Englishfȳlan(“to befoul, defile, pollute”) and fūlian(“to foul”), both from Proto-West Germanic*fūlijan(“to make dirty, befoul”), from Proto-Germanic*fūlijaną(“to make dirty, befoul”), from *fūlaz(“dirty, foul; rotten”), from Proto-Indo-European*puH-(“foul; rotten”).
1549 April 22 (Gregorian calendar), Hughe Latymer [i.e., Hugh Latimer], Augustine Bernher, compiler, “[27 Sermons Preached by the Ryght Reuerende Father in God and Constant Matir of Iesus Christe, Maister Hugh Latimer,[…].]The Syxte Sermon of Maister Hugh Latymer, whiche He Preached before K. Edward [VI], the XII. Day of Aprill.”, in Certayn Godly Sermons, Made uppon the Lords Prayer,[…], London:[…]John Day,[…], published 1562, →OCLC, folio 71, verso:
[…] It is an euil birde that defiles his owne neſt, […]
At mankind's feast, I take my place / In solemn, sanctimonious state, / And have the air of saying grace / While I defile the dinner plate.
1911 October, Charlotte Perkins Gilman, “The Journey”, in The Forerunner: A Monthly Magazine, volume II, number 10, New York, N.Y.: Charlotte Perkins Gilman, →OCLC, page 271, column 1:
“That's only dirt—it will brush off.” But he looked at me with his haggard hopeless eyes and said— “It is mud. Black, slimy, horrible mud. I am defiled.”
[T]here is no thynge with outt a man that can diffyle hym when hitt entreth in to hym⸝ but thoo thyngꝭ [things] which procede out of a mã [man] are thoſe which defyle a mã.
Chr[istian]. VVhy, I tro you did not conſent to her deſires?/Faith[full]. No, not to defile my ſelf; for I remembred an old vvriting that I had ſeen, vvhich ſaith, Her ſteps take hold of Hell.[Proverbs 5:5] So I ſhut mine eyes, becauſe I vvould not be bevvitched with her looks:[Job 31:1] then ſhe railed on me, and I vvent my vvay.
And all yͤ chiefe amonge the preſtes, and the people, multiplyed their ſynnes, acordinge to all the abhominacions of the Heythen, and dyfyled the houſe of the LORDE, which he had ſanctified at Jeruſalem.
What ſo euer crepeth vpon earth, ſhall be an abhominacion vnto you, and ſhal not be eaten. […] Make not youre ſoules abhominable, and defyle you not in them, to ſtayne youre ſelues: for I am the LORDE youre God. Therfore ſhal ye ſanctifie youre ſelues, that ye maye be holy, for I am holy. And ye ſhal not defyle youreſelues on eny maner of crepynge beeſt, that crepeth vpon earth:[…]
VVhat Tongue can ſpeak the reſtleſs Monarch's VVoes;/ VVhen GOD, and Nathan vvere declar'd his Foes?/ VVhen ev'ry Object his Offence revil'd, / The Husband murder'd, and the VVife defil'd, / The Parent's Sins impreſs'd upon the dying Child?
The ſecond offence, more immediately affecting the perſonal ſecurity of individuals, relates to the female part of his majeſty's ſubjects; being that of their forcible abduction and marriage; which is vulgarly called ſtealing an heireſs. For by ſtatute 3 Hen. VII. c. 2. it is enacted, that if any perſon ſhall for lucre take any woman, maid, widow, or wife, having ſubtance either in goods or lands, or being heir apparent to her anceſtors, contrary to her will; and afterwards ſhe be married to ſuch miſdoer, or by his conſent to others, or defiled; ſuch perſon, and all his acceſſories, ſhall be deemed principal felons:[…]
Come recreant, come thou childe, / Ile vvhippe thee vvith a rodde. He is defil'd, / That dravves a ſvvord on thee.
1708 December 15 (Gregorian calendar; date written), [Jonathan Swift], A Letter from a Member of the House of Commons in Ireland to a Member of the House of Commons in England, Concerning the Sacramental Test, London:[…]John Morphew[…], published 1709, →OCLC, page 7:
[H]is Character may be Defiled by ſuch Men and dirty Hands as thoſe of the Obſervator, or ſuch as employ him, […]
1672 January 16 (Gregorian calendar), Joseph Caryl, “Sermon II”, in The Nature and Principles of Love, as the End of the Commandment.[…], London:[…] John Hancock, Senior and Junior,[…], published 1673, →OCLC, page 79:
[Y]ou vvill find if you do not daily ſvveep you houſes, they vvill defile; and the cob-vvebs they vvill grovv; the Spiders vvill be at vvork; and though your hearts be never ſo pure, Spiders vvill creep into them, […]
There is a thing Harry, vvhich thou haſt often heard of, and it is knovvne to many in our land by the name of pitch. This pitch (as ancient vvriters do report) doth defile, ſo doth the companie thou keepeſt:[…]
The verb is borrowed from Frenchdéfiler(“to march; to parade”), from dé-(prefix indicating actions are done more strongly or vigorously) + one or both of the following:[9]
file(“line of objects placed one after the other, file”), from filer (see above), or fil(“thread, yarn; wire”), from Old Frenchfil, from Latinfīlum (see above).
Several bodies of troops defiled towards the frontiers under various pretences; and the whole being ſuddenly aſſembled, formed an army with which the duke of Guiſe [Francis, Duke of Guise] made an unexpected march towards Calais.
VVe had one dangerous Place to paſs, vvhich our Guide told us, if there vvere any more VVolves in the Country, vve ſhould find them there; and this vvas in a ſmall Plain, ſurrounded vvith VVoods on every Side, and a long narrovv Defile or Lane, vvhich vve vvere to paſs to get through the VVood, and then vve ſhould come to the Village vvhere vve vvere to lodge.
Conſtantine had taken poſt in a defile about half a mile in breadth, between a ſteep hill and a deep moraſs, and in that ſituation he ſteadily expected and repulſed the firſt attack of the enemy.
[T]hese granite hills, thousands of feet high, were impracticable for heavy troops: the passes through them being formidable defiles, very costly to assault or cover.
The next morning the enemy were on the march before him, seized the defiles, blocked the fords of the rivers, destroyed the bridges, and sent out cavalry to patrol the open ground, so as to oppose the Athenians at every step as they retreated.
1962 January, “Motive Power Transition on the Kyle Line”, in Modern Railways, Shepperton, Surrey: Ian Allen Publishing, →ISSN, →OCLC, photograph caption, page 17:
On the final stages of the run from Inverness Class 5 4-6-0 No. 45066 winds its train through narrow rock defiles alongside Loch Carron at the approach to Kyle of Lochalsh.
2023 November 15, Dr Joseph Brennan, “A crucial part of our nation's defences”, in RAIL, number 996, page 60:
"For the first time in 125 years a powerful enemy was now established across the narrow waters of the English Channel. ... Many people must have been bewildered by the innumerable activities all around them. They could understand the necessity for wiring and mining the beaches, the anti-tank obstacles at the defiles, the concrete pillboxes at the cross-roads, the intrusions into their houses to fill an attic with sandbags, on to their golf-courses or most fertile fields and gardens to burrow out some wide anti-tank ditch." So wrote Winston Churchill in Their Finest Hour, published in 1949.
The verb is borrowed from Frenchdéfiler(“to arrange soldiers or fortify (something) as a protection from enfilading fire; to unthread”) (compare Middle Frenchdesfilher(“to unthread”)), from dé-(prefix meaning ‘not’) + enfiler(“to rake with gunfire, enfilade; to string on to a thread; to thread (a needle)”) (from en-(prefix meaning ‘in, into; on, on to’) + filer(verb) or file(noun); see etymology 2).[11]