Extensional (Adjective)
Meaning
Defining a word by listing the class of entities to which the word correctly applies.
Classification
All adjective clusters.
Examples
- The definition of "bachelor" is extensional because it is defined as any unmarried male of a certain age or above, regardless of any other properties he may have.
- Dictionaries that define words using extensional definitions rely on categorization rather than analysis of the word's meaning.
- The term "even number" can be defined extensionally as the set of all numbers that can be divided by 2 without leaving a remainder.
- Extensional definitions can sometimes be problematic when dealing with ambiguous or rare instances, such as defining the word "bird" to include penguins.
- By defining "planet" extensionally as a set of specific celestial bodies in our solar system, we may exclude other similar bodies discovered in the future.