boundaries Overview Usage examples Similar and opposite words Pronunciation Dictionary Definitions from Oxford Languages · Learn more bound·a·ry /'bound(?)re/ noun plural noun: boundaries a line that marks the limits of an area; a dividing line. "the eastern boundary of the wilderness" Similar: border frontier borderline partition dividing line bounding line bounds confines limits outer limits extremities margins edges fringes periphery perimeter circumference rim circuit marge bourn skirt a limit of a subject or sphere of activity. "a community without class or political boundaries" Similar: dividing line divide division borderline demarcation line line of demarcation cutoff point threshold limits parameters bounds outer limits confines extremities barriers thresholds ambit compass Feedback