Castellorum Operatio
A New Law Dictionary and Glossary · Alexander M. Burrill · 1850
A New Law Dictionary and Glossary
Lat. In Saxon and old English law. Castle work. Service and labor done by inferior tenants for the building and upholding castles, and public places of defence. One of the three necessary charges, (trinoda necessitas) to which all lands among the Saxons were expressly subject.
Cowell, JSTennett's Par, Ant, 114.
See Trinoda necessitas,