chalk
n.— « The following information is placed on a 3×5 inch index card and handed to the pilot by the chalk leader. This serves as a contract between the pilot and the chalk of soldiers to ensure coordination of LZ data. In case the chalk lands in a different LZ, the pilot will write the grid of the new LZ and hand the 3×5 card back to the chalk leader before the soldiers exit the helicopter.» —by Dept. of Army 101st Airborne Division (Air Assault) Gold Book (Fort Campbell, Ky.) Feb. 4, 1999. (source: Double-Tongued Dictionary)
Further reading
What if, instead of being an inanimate object, a dictionary were alive? That’s the idea behind a lavishly illustrated new children’s book called The Dictionary Story (Bookshop|Amazon) by Oliver Jeffers and Sam Winston. This is part of a...
Janet in Montgomery, Alabama, reports that a day after she had surgery on her hand, the wound burst open, and a doctor noted that her wound dehisced. She’s used to hearing dehisce used in botany to mean the splitting of a plant structure to...