Plural of fort: structures with strong walls built to protect soldiers and supplies, or a child's playhouse made from blankets and pillows.
From Latin 'fortis' (strong), 'fort' entered English from French 'fort', referring to reinforced military structures.
Hudson's Bay Company trading posts were called 'forts' not because they were military, but because the European traders used the term for any permanent structure in unknown territory as a psychological anchor.
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