A room or place where guards or sentries keep watch; a guardhouse or watchtower in a Roman fort.
From Latin excubitorium (ex- 'out' + cubare 'to lie' + -torium 'place for'), a specific architectural term for the quarters where Roman soldiers maintained vigilant guard duty.
Archaeologists still use this Latin term when discussing Roman military architecture because English has no perfect single word for this specific type of guard station.
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