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