Chartroom

Part of speech: noun

Definitions

1. A compartment aboard a vessel where nautical charts, maps, and navigational instruments are stored and consulted for route planning
2. A space on a ship dedicated to maintaining and using maritime charts and navigational equipment for steering and plotting courses
3. The cabin or room on a boat where sailors keep and reference navigation charts and related instruments for determining position and direction

Etymology: "Chartroom" is a compound of "chart" and "room," and its most interesting feature is that it is a near twin of "cardroom," a word that reaches back to a different kind of map. The two words are doublets in the sense that they grew from the same underlying idea but took different routes into English, one through "chart" and one through "card," which were once variant spellings of the same word. Both ultimately descend from the Latin "charta," meaning a sheet of papyrus or paper, which is also where "card" in the sense of a stiff sheet of paper comes from. Over time the two forms split apart in meaning and spelling. "Card" came to dominate for stiff paper and playing cards, while "chart" settled into its modern sense of a map or diagram. A chartroom is therefore a room where charts, the navigational maps of the sea, are kept and consulted, most often on a ship or in a naval or maritime setting. The word is built plainly from its parts, so nothing about its formation is hidden.