A castellumCharlton T. Lewis, Charles Short, A Latin Dictionary in Latin is usually:
a small Roman fortlet or tower,C. Julius Caesar, Gallic War; 2,30 a diminutive of ('military camp'), often used as a watchtower or signal station like on Hadrian's Wall. It is distinct from a , which is a later Latin term that was used particularly in the Germanic provinces. a distribution, header, and settling tank for municipal water in a Roman aqueduct (known as a castellum aquae/castellum divisorium).
It is the source of the English word "castle".
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