Temporary camps or settlements, especially military ones; the places where people have set up temporary shelters.
From encamp + -ment (suffix forming nouns of result or action) + -s (plural). A 'ment' noun describes the result or place of an action.
The American Civil War is full of 'encampments'—the word specifically means the temporary PLACE where an army set up, not just the act of camping. It's the noun form that historians still use today!
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