A definition is a statement of the meaning of a term (a word, phrase, or other set of symbols).[a] The term to be defined is the definiendum. The term may have many different senses and multiple meanings. For each meaning, a definiens is a cluster of words that defines that term (and clarifies the speaker's intention).A definition will vary in aspects like precision or popularity. There are also different types of definitions with different purposes and focuses (e.g. intensional, extensional, descriptive, stipulative, and so on).A chief difficulty in the management of definitions is the necessity of using other terms that are already understood or whose definitions are easily obtainable or demonstrable (e.g. a need, sometimes, for ostensive definitions).A dictionary definition typically contains additional details about a word, such as an etymology and the language or languages of its origin, or obsolete meanings.