(~s)
1.
A ~ is a non-commissioned officer of middle rank in the army, marines, or air force.
A ~ with a detail of four men came into view.
...Sergeant Black.
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2.
In the British police force, a ~ is an officer with the next to lowest rank. In American police forces, a ~ is an officer with the rank immediately below a captain.
The unit headed by Sergeant Bell.
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