I ran across this word reading a book, and was so shocked by it that I just had to look it up. I had absolutely no idea what the root word was, or what it related to, and its context didn't provide any clues. The definition from Merriam-Webster reads:
Main Entry: ter·a·tol·o·gy
Date: circa 1842
The study of malformations or serious deviations from the normal type in developing organisms
The way it was used was in relation to politics, and it was discussing the formation of a political movement. I thought it very clever! Anyway, had to share that. I found it while reading the book "Seeing", by José Saramago. So far, it's really dry, and I swear the guy doesn't believe in paragraph breaks -- I'll have to write a review later, if I can get through it.