Editing Circular definition (section)

===Pragmatic===
From a pragmatic point of view, circular definitions may be characterised in terms of new, useful or helpful information: a definition is deficient if the audience must either already know the meaning of the key term, or if the term to be defined is used in the definition itself. Such definitions lead to a need for additional information that motivated someone to look at the definition in the first place and, thus, violate the principle of providing new or useful information.<ref>Wierzbicka, A., ''Semantics: Primes and Universals''. Oxford University Press: 1996.</ref> Here are some examples:

* Suppose we define "[[oak]]" as a [[tree]] which has [[catkin]]s and grows from an acorn, and then define "acorn" as the [[nut (fruit)|nut]] produced by an oak tree. To someone who does not know which trees are oaks, nor which nuts are acorns, the definition is inadequate.
* If someone wants to know what a [[cellular phone]] is, telling them that it is a "phone that is cellular" will not be especially illuminating. Much more helpful would be to explain the concept of a cell in the context of telecommunications, or at least to make some reference to portability.
* Similarly, defining [[dialectical materialism]] as "materialism that involves dialectic" is unhelpful.

Consequently, when constructing systems of definitions, authors should use good practices that avoid producing viciously circular definitions. In many learner's dictionaries, circular definitions are greatly reduced by writing definitions using only the words in a constrained [[defining vocabulary]].<ref>Bullock, D. 'NSM + LDOCE: A Non-Circular Dictionary of English', ''International Journal of Lexicography'', 24/2, 2011: 226-240</ref>