I’ve already gotten some good response to my last post about reading through Greek Isaiah in a year. More on that again soon.
For now, to whet all our appetites, I’ve just been able to use Accordance Bible software to generate this list.
VOCABULARY IN LXX ISAIAH (Rahlfs) (PDF)
It lists all the words in Isaiah, with their glosses (brief “definitions”), that occur 100 times or less in the Septuagint (Rahlfs). It also shows how many times that word occurs in Isaiah itself.
I used a multi-step process to compile this from Accordance. I’m sure there’s a more elegant way to do what I did, but I am happy to have this list, and know I’ll use it for less than frequently occurring LXX vocabulary when reading through Isaiah, starting December 2.
UPDATE: If you want to join along, here’s the central place on Facebook for discussion, helpful files, questions, companions, etc.
Words on the Word 
Thanks for your Vocabulary of Isaiah in the LXX. I am reading the Greek OT & NT this year. The last time I read the LXX was in 1978! I will be reading the whole LXX, but this will help when I get to Isaiah. It is interesting to see how many of these words are familiar from reading the NT and how many can be figured out from word parts (roots, prefixes, etc.)
That’s great! Thanks for letting me know, and I’m glad the list will help. Happy/blessed reading to you!