Just a quick list of words not found in the US English dictionary (v.25):
draught, draughts
accoutrement, accoutrements
neurotoxin
noir
Not terribly difficult to add, but I keep checking them in Word to be sure I’m not missing something.
Ed
Got it. The US English dictionary appears to be catching “accoutrement” when I test this, but none of the others. Which is funny since Webster confirms that the word is usually used in the plural, so you’d think it would prefer “accoutrements” if it was only going to accept one. Go figure.
For those interested, my compiled “missing dictionary words” looks like this:
US Dictionary
accoutrements
amongst
backwards
draught, draughts
enquiry
forwards
gauge
glamour
greaves
hewn
leapt
neurotoxin
noir
okay
panoptic
panopticon
Rebecca (because several less common spellings are already in there)
telepath
terracotta
towards
upwards
vera (as in aloe vera)
ziggurat, ziggurats
UK Dictionary
accoutrements
amongst
backwards
dreamed
forwards
greaves
hewn
inquiry
leapt
neurotoxin
noir
okay
panoptic
panopticon
practice
Rebecca (because several less common spellings are already in there)
telepath
terracotta
towards
towards
upwards
vera (as in aloe vera)
ziggurat, ziggurats
(Except when people specifically type them up and I copy them to the list, I haven’t included plural forms here.)
Shouldn’t that be, “Hello Vera.”
Sorry.
I finally managed to find a few minutes to investigate adding new words to the Aspell dictionaries - it actually works out to be pretty simple. I have already added the words listed thus far and they will appear in the next release of Scrivener (beta 026 is the current version as of posting this). Below is a set of instructions for those brave enough to open a command prompt and download a free plain text editing tool like Notepad++ - Windows Notepad will not do it without pain.
I’ve also attached four files (zipped) for users who can’t wait, and can’t be bothered with command prompt. You just need to detach these files into the Aspell\Dict directory within Scrivener. You must overwrite the existing two en_US.multi and en_UK.multi files. Then restart Scrivener and the new words will all be recognised.
Augmented Dictionary Files US & GB.zip (1.66 KB)
I would still appreciate if the word list of this post is continually augmented as it will make it easier at release time just to pull the full list and add the words. So, please continue the good work here Jennifer and co 
Here are the instructions for doing it yourself:
- Create a file list named yourlist.txt. Add words, one per line, to yourlist.txt.
c:\Program files\Scrivener\Aspell\bin\yourlist.txt i.e. your list might
look like:-
malondialdehyde
neuropsychology
Silybin
vagus
- Convert file list to an Aspell word list.
This command creates an Aspell wordlist with the en_US language specification (en_GB is another example):
Move to the following directory with a command prompt:
cd c:\Program files\Scrivener\Aspell\bin
Type the following command and then press Enter:
aspell --lang=en_US create master yourlist.rws < yourlist.txt
- To finish adding it to the dictionary change into the dictionary directory by running the following:
c:\Program files\Scrivener\Aspell\dict
Then edit the following file with Notepad++: en_US.multi
Then add the following on a new line at the end of the file:
add yourlist.rws
Restart Scrivener and your words will now be updated in the main Aspell dictionary
Thank you for those instructions, that’s very helpful.
Still in the interest of making the default included dictionaries the best they can be you can add “learned” to the words missing from the UK dictionary.
Edit: It is perhaps a good idea sticky this thread as I see others asking questions about missing words now and then and it might be good to have one obvious place to add your missing words to and to check what has already been discovered by others.