Definition: A Practical Guide to Constructing and Evaluating Definitions of Terms

Definitions matter. They determine who can get married, when the organs of a “dead” person can be harvested for transplants, what counts as a planet, the unemployment rate, and more. "Definition" pro- poses criteria and guidelines for constructing and evaluating defini- tions, with reference to the definer’s basic purpose (reporting, stipu- lating, or advocating a meaning), the definition’s content (the kinds of words used and the information conveyed), and its form (any of 14 kinds). The proposals of criteria and guidelines implicitly address theoretical issues and are illustrated by definitions of 166 2 terms taken from many fields—terms such as ‘clock,’ ‘life,’ ‘planet,’ and ‘thrombin activatable fibrinolysis inhibitor.’