What's the plural form of prosiness? Here's the word you're looking for.
Answer
The noun prosiness can be countable or uncountable.
In more general, commonly used, contexts, the plural form will also be prosiness.
However, in more specific contexts, the plural form can also be prosinesses e.g. in reference to various types of prosinesses
or a collection of prosinesses.
Examples
Durling's 1976 scholarly prose translation and it shows, in both the clarity and the prosiness of his versions.
While many of his contemporaries took poetry toward prosiness, he cultivated what turned out to be a dazzling talent for rhyme.