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1. The size of something as given by the distance around it
   - perimeter
    
2. The boundary line encompassing an area or object
   "a danger to all races over the whole circumference of the globe"; "he had walked the full circumference of his land";
   - circuit
    
3. The length of the closed curve of a circle

Derived forms: circumferences

Type of: border, borderline, boundary line, delimitation, length, mete, size

Encyclopedia: Circumference