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