Castle-guard \Cas"tle-guard`\, n.
1. The guard or defense of a castle.
[1913 Webster]
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.
[1913 Webster]
3. A feudal tenure, obliging the tenant to perform service
within the realm, without limitation of time.
[1913 Webster]