From Middle French chaton, chaston, from Old French chastun (“the projecting part of a ring embedded with a stone”), from Frankish *kastō (“box, case”), from Proto-Germanic *kastô, *kasô, *kasą, *kazą (“vessel, container, pitcher, barrel”). Cognate with Old High German kasto (“box, case”) (Modern German Kasten), Dutch kast (“cupboard, case”), Old English castenere (“cabinet, chest”), Old Norse kass, kassi (“basket”), Gothic 𐌺𐌰𐍃 (kas, “vessel, container”), Old High German char (“vessel, bowl, tray, trough”), Middle Low German kar (“vessel, basket”), Old Norse ker (“vessel, container”).
chaton m (plural chatons)
- collet, beazle (around a jewel, on a ring)
- (by extension) the jewel itself (around which the collet is, on a ring)