(封建时期)佃农守城的义务,免除此义务所纳的税
Castle-guard \Cas"tle-guard`\, n. 1. The guard or defense of a castle. 2. (O. Eng. Law) A tax or imposition an a dwelling within a certain distance of a castle, for the purpose of maintaining watch and ward in it; castle-ward. 3. A feudal tenure, obliging the tenant to perform service within the realm, without limitation of time.