Definitions for "Michaelmas"
The feast of the archangel Michael, a church festival, celebrated on the 29th of September. Hence, colloquially, autumn.
Feast of St. Michael on 29 Sept. (MEDIEV-L. Medieval Terms)
Term October-December - Michaelmas
Michaelmas (1977) is a science fiction novel by Algis Budrys. The eponymous protagonist is an ex-hacker who had early in the computer era left "back doors" in many key pieces of software which run vital government and commercial computers. As a result, by the turn of the millennium, he has become one of the most powerful men on earth, because of his ability to spy and influence through the world wide computer network.