I am a computer expert who loves a challenge. When I am not managing servers and fixing flaws, I write about it and other interesting things on various blogs.
a small Roman fortlet or tower, a diminutive of castrum ("military camp"), often used as a watchtower or signal station e.g. on Hadrian's Wall. It should be distinguished from a burgus, which was a later Latin term used particularly in the Germanic provinces.
a settling or storage tank in a Roman aqueduct or it:castellum aquae.