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Contributors:Mark Pepper, Dana Lynn Driscoll.
Summary:

This handout provides suggestions and examples for writing definitions.

Writing Definitions

A formal definition is based upon a concise, logical pattern that includes as much information as it can within a minimum amount of space. The primary reason to include definitions in your writing is to avoid misunderstanding with your audience. A formal definition consists of three parts.

  1. The term (word or phrase) to be defined
  2. The class of object or concept to which the term belongs.
  3. The differentiating characteristics that distinguish it from all others of its class

For example:

Although these examples should illustrate the manner in which the three parts work together, they are not the most realistic cases. Most readers will already be quite familiar with the concepts of water, comic books, and astronomy. For this reason, it is important to know when and why you should include definitions in your writing.

When to Use Definitions

Additional Tips for Writing Definitions