1. The mistress or female owner of a castle or large country house.
Usage: Often used in historical or formal contexts
2. A woman in charge of a castle or large household; the wife of a châtelain (castle lord).
Usage: Historical term, primarily European
3. A decorative chain or clasp worn at the waist, typically used to hold keys, a watch, or other small items.
Usage: Fashion/accessory sense; less common in modern usage

Examples

• The chatelaine of the castle welcomed guests to the grand hall.
• As chatelaine, she managed the household staff and oversaw all domestic affairs.
• The medieval chatelaine held considerable authority over the estate during her husband's absence.
• She wore an ornate chatelaine at her waist, from which hung her keys and a small watch.
• The novel's protagonist becomes the chatelaine of a sprawling French château.
• In historical records, the chatelaine was often as powerful as the lord himself.