from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The master of a castle; a castellan.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. castle-keeper, castellan
from The Century Dictionary and Cyclopedia
- n. A castellan.
- n. In France, formerly, a territorial lord who had the right of possessing a castle.
Middle English chatelein, from Old French chastelain, from Latin castellānus, from castellum, castle; see castle.(American Heritage® Dictionary of the English Language, Fourth Edition)
From French châtelain, itself from château ("castle") (Wiktionary)