Definition

Definition

A definition is a statement of the meaning of a concept.

Note

Rules for definitions can be found in ISO 704.

Generic relations

Superordinate concept in the generic relation is:

• Statement

Subordinate concepts are:

• Intensional definitions
• Extensional definitions

Characteristics

• Conciseness
• Unambiguity
• Clarity

Rules

1. A definition is composed of a statement explaining what the concept 'is', not what it refers to of describes. Correct: An apple tree is a tree....
2. A definition is reflects the concept system describing the concept and its relations to other concepts in the system. The characteristics used in the definition should therefore be selected to indicate the connection between the concepts or the delimation that distinguish one concept from another. Correct: An apple tree is a tree that bears apples. Apple tree is a subordinate concept of a tree and both are part of a concept system.
3. A definition is as brief as possible and as complex as necessary. Additional information is inclused in a note. Incorrect: An apple tree is tree that bears apples with the purpose of being harvested.
4. A definition is valid it it can replace a term in a text without loss of or change in meaning.

Don'ts

1. Defintition is circular. Incorrect: A chair is a chair on which you can sit.
2. Defintion is too broad. Incorrect: An apple tree is a living organism.
3. Definition is too narrow. Incorrect: An apple tree is a tree that bears Golden Delicious apples.
4. Definitions is negative. A definition describes what it is, not what it is not. Incorrect: An apple tree is not a pear tree.