marring

1. gerundparticiplepresentpresent participle and gerund of mar: ruining, thwarting, spoiling.

   […]Hath all his ventures fail'd? What, not one hit? From Tripolis, from Mexico, from England, From Lisbon, Barbary, and India? And not one vessel scape the dreadful touch Of merchant-marring rocks?

   c. 1596–1598 (date written), William Shakespeare, “The Merchant of Venice”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act III, scene ii]

plural marrings

1. Something that mars or spoils; a blemish.

   Unable to read even as much of them as the scamps who wrote them and could read nothing more, the smuggler had finally trained himself to ignore them; they were marrings to be overlooked while the eye was out for other, more meaningful detail.

   1985, Samuel R. Delany, Flight from Nevèrÿon