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1. The line or plane indicating the limit or extent of something
   - bound, bounds
    
2. A line determining the limits of an area
   - edge, bound
    
3. The greatest possible degree of something
   "to the boundary of his ability"
   - limit, bound

Derived forms: boundaries

See also: bound

Type of: extent, extremity, line

Encyclopedia: Boundary, Derbyshire Boundary Boundary, Staffordshire Boundary, Leicestershire