A small key with a square tube to fit the winding-arbor of a watch, serving to wind the watch by coiling the main-spring.(noun)
The Century Dictionary (Public Domain)
Use "watch-key" in a sentence
"His step-father still wore, after the fashion of the Empire, his watch in the fob of his trousers, from which there depended over his abdomen a heavy gold chain, ending in a bunch of heterogeneous ornaments, seals, and a watch-key with a round top and flat sides, on which was a landscape in mosaic."
"A watch-key pressed firmly on the point stung by a scorpion extracts the poison, and a mixture of fat or oil and ipecacuanha relieves the pain."
"Another, a tall man, lies on a sofa beside a table on which are empty bottles, and plays with his watch-key."