This seems like a basic question, but I can't find an answer to it:
As far as I know, 美化語 refers to the ご・お・etc. prefix on words for mere beautification. However, I have seen some ambiguity in its usage, and now I am wondering: is the ご・お・etc. prefix that words take in the 尊敬語・謙譲語 conjugations also referred to as 美化語？ How about the お in cases where it has been lexicalized, or nearly so (e.g. お休み、お八つ)?