What term is used to describe something that lacks clarity or sharp demarcation?

The term that describes something that lacks clarity or sharp demarcation is often interpreted as "fuzzy." This term is widely used in various contexts, including mathematics and philosophy, to denote concepts that are not precisely defined or that have uncertain boundaries.

A "fuzzy" concept does not adhere to strict definitions and allows for a spectrum of interpretations or values, capturing the idea that some things exist in degrees rather than absolutes. For instance, in fuzzy logic, truth values can range between fully true and fully false, which parallels the notion of lack of sharp boundaries.

In contrast, terms like "vague" or "ambiguous" also denote a lack of clarity, but they do not specifically capture the idea of "sharp demarcation." "Vague" usually refers to something that is not clearly expressed or defined, while "ambiguous" often involves at least two possible interpretations that lead to uncertainty. Therefore, while "vague" might be an understandable choice, it does not emphasize the nuanced gradation and the lack of clear-cut distinctions in the same way that "fuzzy" does.