[ ka-stel-uh m ]
/ kæˈstɛl əm /

noun, plural cas·tel·li [ka-stel-ahy] /kæˈstɛl aɪ/. Archaeology.

a small isolated fortress, or one of a series of such fortresses, of the ancient Romans.

Origin of castellum

< Latin: fortified settlement, fortress < *casterlom < *castṛlom < *castrelom, equivalent to castr(a) (neuter plural) fortified camp + *-elom diminutive suffix; see -ule, -elle Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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