Here's a fun place to look up modern slang, but be aware that the definitions aren't particularly kind or appropriate:
I used to look up all the words I didn't know, hoping to sneak them into everyday conversation. I gave up on the list at 22 pages, since I couldn't figure out how to use words like "weet"--to know, as in, "I weet it." People don't really need a name for the handle of a scythe (a snath). Some archaisms die, and that's not bad.
Now I'm using a boggle solver to check if the longest word is the final word of the square, as when "ground" is listed and "playground" is still not mentioned yet*. If I'm lucky enough to get a big score, I can tell if it's likely to stay that way until 50 plays. (The dictionaries are not exactly the same, with nesses and lesses not used with such frequency and other differences, too.)
*Of course, that's not the compound word I found--you have to figure that out yourself!