What's the plural form of extendedness? Here's the word you're looking for.
Answer
The noun extendedness can be countable or uncountable.
In more general, commonly used, contexts, the plural form will also be extendedness.
However, in more specific contexts, the plural form can also be extendednesses e.g. in reference to various types of extendednesses
or a collection of extendednesses.
