boundary

1 a real or imaginary point beyond which a person or thing cannot go parents have to set boundaries for their children, and the children want them to Synonyms bound, limit, cap, ceiling, confines, end, extent, limitation, line, terminationRelated Words extremity, fag end, terminus; border, brim, edge, margin, rim, verge; outside; bar, barrier, fence, hedge, restraint, stop, wall

2 the line or relatively narrow space that marks the outer limit of something that chalk line marks the boundary of our playing field Synonyms borderline, bound, border, brim, circumference, compass, confines, edge, edging, end, frame, fringe, hem, margin, perimeter, periphery, rim, skirt, skirting, vergeRelated Words ambit; brink, crest, curb, cusp, lip; ceiling, maximum; demarcation, extent, limitation, measure, mere, restriction, termination; borderland, frontier, march, outskirts, pale, selvage; lap; shoreNear Antonyms center, core, heart; inner, inside, interior, middle, within