The act of surrounding or enclosing something completely, or a military tactic of surrounding an enemy force to trap them.
From 'encircle' (to form a circle around) plus the noun suffix '-ment'. The root 'circle' comes from Latin 'circulus' (ring).
In military history, the encirclement is one of the most devastating tactical maneuvers—Hannibal's encirclement of Roman forces at the Battle of Cannae in 216 BC is still studied in military schools as the perfect example of how a smaller force can destroy a larger one by surrounding them completely.
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