I own a copy of 'How to Increase Your Word Power.' I have a 'Word of the Day' delivered to my email. I use words like 'fractious' and 'ubiquitous' when I'm talking, and I use them in correct context. I understand the synonyms that I pluck from the thesaurus and plunk in my papers. I read books on punctuation for fun.
The American Heritage Dictionary published a list of 100 words every high school graduate should know. High school graduate. Not double-major-BA-valedictorian-going-back-for-another-BA graduates. High school. Grade 12.
I could define maybe half the words to a nine-year-old (a true test of whether or not you really know what they mean) and could use about three quarters of them in sentences (which only means you've heard them before).
Sometimes I think I need to get out more, but other times I figure I should stay in and read the dictionary. I've got some catching up to do.