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