Extensional is a term used to describe something that extends or stretches outward. The antonyms for extensional would be words that describe things that are inward or contracted. Some possible antonyms for extensional include "intensional," "narrow," "restricted," "constrained," "limited," and "finite." These words all suggest that something is contained or restricted in some way. For example, an intensional approach might focus on the internal characteristics of a concept or idea, while a narrow approach would focus on just one aspect of something rather than taking a more expansive view. By contrasting extensional with these other terms, we can better understand what it means to extend outwards and push beyond boundaries or constraints.