Thanks to Kcit for an enjoyable and testing challenge. I doubt that I will find much use in conversation for some of the new words I learned but none the worse for that!
To my shame, I fell hook, line and sinker for the gender misdirection in the “Inheritor” clue. And I spent far too long trying to see a way of producing the thematic word in one of the 12 cell spaces before light dawned.