Hello. First of all, thank you for making this wonderful piece of software. It makes my writing a pure joy!
I write sci-fi/fantasy novels. As such, I often have words that I create for my stories. These can be names, places, events, anything. Of course, they are not recognized by any spell checker. I know that, in Scrivener, I can right click on a “misspelled” word and click Learn Spelling. However, I would like to be able to do more.
When using MS Word, I am able to create a custom dictionary (or dictionaries) to use alongside the general dictionary. In this custom dictionary I can add all of my unusual terms in all of their forms (singular, plural, possessive, etc) and thus spell check for them. Because I can create custom dictionaries (naming them) I can assign them to different projects. For example, I wrote a novel called The Dreamshift Chronicles. During its writing, I made a custom dictionary called DSC. All of my words, unique to that novel, including figures of speech used by a particular character, were included and, thus, I could spell check for them. When working on a different book, I could remove the custom dictionary, add a different one, or create a new one if I wanted to.
I would like to be able to do this in Scrivener. Sure, these words are made up, but even the author can mistype them. So being able to spell check our made up words is important. 
Thank you for your consideration.
