Neighboring or bordering on all sides; surrounding or adjacent in the area around something.
From Old French circumvoisin, combining circum- 'around' with voisin 'neighbor' (from Latin vicinus). This is an archaic English term that survives in legal and historical documents describing neighboring territories.
Medieval documents describe circumvoisin lands and kingdoms to establish boundaries—it's how people in pre-map eras defined territory by describing the circle of neighbors around you rather than coordinates.
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