Definition of ballium in English:

ballium

noun

  • The defensive wall of a castle, or the area it enclosed; one of a series of such walls or courts.

Origin

Late 18th century; earliest use found in Francis Grose (d. 1791), antiquary. From post-classical Latin ballium outer rampart of a castle, apparently from Anglo-Norman bail, baile and Old French bail (although this is first attested later: see discussion at that entry).

Pronunciation

ballium

/ˈbaliəm/