A word, phrase, or symbolic expression used to define something, especially in a dictionary entry, or introducing a word or symbol into a logical system by providing a statement of its meaning.
- ‘He required of definition that the definiens (the statement of definition) should be synonymous with the definiendum (the expression or concept being defined) but contain no terms in common with it.’
- ‘The former is defined, by the ancient logic texts I love, as when a definition uses the same terms in the definiens as in the definiendum.’
- ‘The use of the definiens and of the definiendum, violation of a law of nature, both assume that the operation of a law of nature is logically compatible with the occurrence of an exception to its operation.’
- ‘Consider as a definiendum a universal, such as man, and its definiens, rational animal.’
- ‘This, of course, is Moore's open question argument. ‘If ‘good’ was definable it was a complex, and so it could be asked of any definiens if it was good.’
Late 19th century from medieval Latin, ‘defining’, present participle of definire (see define).