- The boundary line of a circle.
- The boundary line of a figure, area, or object.
- (Abbr. c or circ.) The length of such a boundary.
[Middle English, from Old French circonference, from Latin circumferentia, from circumferēns, circumferent-, present participle of circumferre, to carry around : circum-, circum- + ferre, to carry.]
circumferential cir·cum'fer·en'tial (-fə-rĕn'shəl) adj.SYNONYMS circumference, circuit, compass, perimeter, periphery. These nouns refer to a line around a closed figure or area: the circumference of the earth; followed the circuit around the park; stayed within the compass of the schoolyard; the perimeter of a rectangle; a fence around the periphery of the property.




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series expansion is used to find the actual value:



