TOMBSTONE

gravestone, headstone, tombstone

(noun) a stone that is used to mark a grave

Source: WordNet® 3.1

Etymology

Noun

tombstone (plural tombstones)

A headstone marking a person's grave.

Synonyms: headstone, gravestone

(mathematics) The symbol "∎" marking the end of a proof.

Synonym: halmos

(computing, Microsoft Windows) A marker that takes the place of deleted data, allowing for replication of the deletion across servers etc.

(computing) A crashdump.

(cardiology) An unusual morphological feature on an electrocardiogram indicative of acute myocardial infarction, characterized by a massive ST elevation.

Verb

tombstone (third-person singular simple present tombstones, present participle tombstoning, simple past and past participle tombstoned)

(UK, intransitive) 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.

(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.

(transitive, computing, Microsoft Windows) To replace (an object or data) with a tombstone marker.