castellorum operatio

/kxstalorsm opareysh(iy)ow/ In Saxon and old English law, castle work. Service and labor done by inferior tenants for the building and upholding of castles and public places of defense. One of the three necessary charges (trinoda necessitas) to which all lands among the Saxons were expressly subject. Towards this some gave them personal service, and others, a contribution of money or goods. 1 Bl. Comm. 263