(Disclaimer: not only I tried googling the answer, I also asked native english speakers, but they couldn't give me a definitive answer).
Basically, In one of my conversations, I said the following sentence:
They haven't contributed much to the world aside zealotness.
Then I got confused, and I realized I don't know what is the "derivative" for this word.
hot -> heat
serious -> seriousness
zealot -> ???
Google remotely suggests zealousness, but it seems that this word actually backs-up the word "zealous" and not "zealot".
So, Is there an actual idiomatic way of saying "zealotness"