Source: The Collaborative International Dictionary of English v.0.48
Chatelaine \Chat"e*laine\, n. [F. ch[^a]telaine the wife of a
castellan, the mistress of a chateau, a chatelaine chain.]
An ornamental hook, or brooch worn by a lady at her waist,
and having a short chain or chains attached for a watch,
keys, trinkets, etc. Also used adjectively; as, a chatelaine
chain.
[1913 Webster]
chatelaine
n 1: the mistress of a chateau or large country house
2: a chain formerly worn at the waist by women; for carrying a
purse or bunch of keys etc.