sh-toint
ADJECTIVE: Having a changeable luster.
NOUN: A chatoyant stone or gemstone, such as the cat's-eye.
ETYMOLOGY: French, present participle of chatoyer, to shimmer like cats' eyes, from chat, cat, from Vulgar Latin *cattus, perhaps of African origin.
OTHER FORMS: cha·toyan·cy —NOUN - AHD4 (a decidedly modern dictionary; see also MW-CD and others -- perhaps you were looking only at the noun form)