Castellanus
Defined in 2 dictionaries — Black's (1910), Burrill (1850)
Black's Law Dictionary
Henry Campbell Black, M.A. · 1910
A castellain; the keeper or constable of a castle. Spelman.
A New Law Dictionary and Glossary
Alexander M. Burrill · 1850
Castellanius, Castellarius. L. Lat. [from castellum, q. v.] In old English law. A castellain; the keeper, captain or constable of a castle. Spelman, voc. Castellum. Bract. fol. 363. See Castellain. An officer of the forest. Manwood, part 1, p. 113. Blount.