Origin of ballium
From Medieval Latin, dating back to 1790–1800, Latinized variant
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for ballium
It stands in a ballium or court, surrounded by a moat and an embankment.
Matilda flew out of the room, and was in an instant in the ballium.
Both these castles are enclosed by a court or ballium, with a fortified entrance, like those erected by the Normans.
From the dark shadows of the ballium, they passed into the moonlit inner court.The Outlaw of Torn
Edgar Rice Burroughs
We next approach, the ballium, or castle yard through the Porter's Lodge of two towers with a portcullis.