Let me say it again (explicitly, now) that personally I have no problem with the word deification. I don't believe we can accept a doctrine by referring to a dictionary (maybe a good theological dictionary or a good volume on systematic theology, or... yes). If that is the case we should get rid of many other terms like Trinity, for example. Every community of people has a personal, special language. Think about doctors, engineers, chemists, and so on. A special term is understood by their group without the need to explain every time what it means.
Many church fathers believed and taught deification. Even the reformers had this doctrine.
In a 1526 sermon Luther said: "God pours out Christ His dear Son over
us and pours Himself into us and draws us into Himself, so that He
becomes completely humanified (vemzenschet) and we become completely
deified (gantz und gar vergottet, "Godded-through") and everything is
altogether one thing, God, Christ, and you."'
"Deification" is part the church's traditional vocabulary...
http://www.ctsfw.net/media/pdfs/marq...andtheosis.pdf
Personally I never told anyone, and I will continue to tell no one, that God became man to make man God/god in life and nature but not in the Godhead.
Many people like to drink coffee but some cannot take in caffeine. Knowing that I prepare a decaf coffee for my friend. Alarmed he says that he cannot drink coffee, because coffee contains caffeine. I tell him that his coffee does not contain caffeine. He replies that coffee is coffee. I repeat that his coffee is decaf. He …. Then I'll serve him orange juice!
(sorry for this bad example, there is not such a thing as 100% decaf coffee. And I am sorry too to bring in this serious discussion such a low example. You can justly scorn me.)