Pronounced: tehr, noun
Notes: Sounds like “tear” (a rip) to me. I’ve run across this word, and kind of knew the meaning from the association, but not fully, and I didn’t know the background.
The word circumvallate means “to surround by a defensive structure, such a a rampart”
This word came into English in the mid-1600s
Background / Comments
I recognized the circum- part of the word (it’s Latin for “around”), but not the second part; it turns out that vallum is Latin for “rampart”. However, given the definition, it seems to me that creating a moat around a castle would qualify as a circumvallating.