First off, drop the "Wicked" bit. Her real name is Theodora, or in L. Frank Baum’s books, Elphaba (an anagram of L. Frank Baum’s initials—L.F.B.). Yeah, the author hid a nickname in a pun.
And here’s a shocker: In the original 1900 novel, she wasn’t green. That’s a 1939 movie invention, probably because director Victor Fleming realized a pale yellow witch wasn’t scary enough to sell popcorn. Margaret Hamilton’s green paint was so toxic it turned her skin green for weeks—she actually had to drink milk to flush it out. Talk about method acting on a budget!