I heard the author of How Shakespeare Changed Everything interviewed on KUOW Tuesday, and since then, I haven't been able to get out of my head the words that Shakespeare invented. They are regular words, words we use all the time.
The list includes alligator, eyeball, and skim milk. He took the existing assassin and made assassination.
Wikipedia says alligator is an adaptation of the Spanish "el lagarta" for lizard. Eyeball and skim (from skimmed) milk seem obvious. Genius always makes sense.
Here are some more.