What is to determine with precision; to mark out with distinctness; to ascertain or exhibit clearly; as, the defining power of an optical instrument. Rings . . . very distinct and well defined. Sir I. Newton called?

define — To determine with precision; to mark out with distinctness; to ascertain or exhibit clearly; as, the defining power of an optical instrument. Rings . . . very distinct and well defined. Sir I. Newton. (Webster's 1913.)

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