A grave marker, a stone slab or similar object marking a person's grave.
True, there's no harm in crying for one's husband, and the tombstone, though plain, was a solid piece of work, and on summer's days when the widow brought her boys to stand there one felt kindly towards her.1922, Virginia Woolf, chapter 2, in Jacob's Room:
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Mathematics, Sciences The symbol "∎" marking the end of a proof.
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Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences A marker that takes the place of deleted data, allowing for replication of the deletion across servers etc.
Microsoft Windows
If you attempt to restore a backup that is older than the tombstone lifetime, it may introduce objects that were deleted […]2008, Laura E. Hunter, Robbie Allen, Active Directory Cookbook, page 739:
This actually results in a crash dump, which is written to the log and to a tombstone file.2014, Joshua J. Drake, Zach Lanier, Collin Mulliner, Android Hacker's Handbook, page 186:
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Cardiology, Medicine, Sciences An unusual morphological feature on an electrocardiogram indicative of acute myocardial infarction, characterized by a massive ST elevation.
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Journalism, Media A printed advertisement in a newspaper or magazine, typically having unadorned centered text in black and white, enclosed in a simple box.
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Art, Arts A museum plaque or caption displaying information about a work of art or exhibited object.
The last bit of information on each tombstone is an accession number—an alphanumeric block that is assigned when an object is added (accessioned) to the museums’ collections.2015, Harvard Art Museum, Writing on the Wall:
"[…] Pity we're not both same size, or I'd steal one of your shirts, for I buried the last of mine yesterday, and here's the tombstone," producing a pawnbroker's duplicate.1862, W. H. Watts, My Private Note-Book; or, Recollections of an old reporter, page 123:
UK To take part in tombstoning: to jump into the sea, etc. from a cliff or other high point so as to enter the water vertically straight.
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Hobbies, Lifestyle, Sports, Surfing For a surfboard to stand upright half-submerged in the water (like a tombstone, above) because the surfer is underwater with his or her legrope pulled tight. Often this indicates a surfer in difficulty, either held down by the power of a wave or unconscious and unable to get to the surface.
Before the contest even started, Slater went down hard in a warmup session. He took a two-wave hold-down in the semifinals, his board tombstoning eerily for all to see, […]2005, Bruce Jenkins, Surfer magazine, (referring to Kelly Slater) http://surfermag.com/features/events/mav05/
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Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences To replace (an object or data) with a tombstone marker.
Microsoft Windows
One of the many improvements in Windows 2000 WINS (and NT4 SP4) is the capability to selectively delete or tombstone records.2000, William Boswell, Inside Windows 2000 Server, page 211: