 Statement that attaches a meaning to a term |
A definition is a semantic statement of the meaning of a term (a word, phrase, or other set of symbols).12 Definitions can be classified into two large categories: intensional definitions (which try to give the sense of a term), and extensional definitions (which try to list the objects that a term describes).3 Another important category of definitions is the class of ostensive definitions, which convey the meaning of a term by pointing out examples. A term may have many different senses and multiple meanings, and thus require multiple definitions.4a
For the definition of another word, see Wiktionary. For other uses of the word "definition" itself, see Definition (disambiguation).
In , a definition is used to give a precise meaning to a new term, by describing a condition which unambiguously qualifies what the mathematical term is and is not. Definitions and form the basis on which all of modern mathematics is to be constructed.