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