www.alphadictionary.com

Reading a history of the reformation last night, I came to the place where Henry VIII made Cranmer his vicegerent with considerable power. At that point the author broke in to admonish his readers not to confuse vicegerent and vice-regent, which of course is easy to do. Though Cranmer had considerable power, it was supposed to be focused on the religious area. So it occurred to me that vicegerent would make a good word of the day.

This is one difficult word to wrap my feeble brain around. It would seem to be simply another word for deputy or even agent. Yet most of the links I've come across make it seem a word much used in Islamic terms. Then again, there are a few that relate it to the Roman Catholic church. It's a tough one, to be sure.