TRIPLE WITCHING HOUR

noun (Business World) Colloquially, the unpredictable final hour of trading on the US stock exchange before three different kinds of options simultaneously expire. Etymology: The witching hour is traditionally midnight, a time when the witches are supposed to come out and anything can happen; the triple witching hour is so called because the market can easily be thrown into turmoil (especially by computer-driven changes) when options are all expiring at once, and anything could happen to the Dow-Jones index. History and Usage: The term has been in use among traders on Wall Street since at least the sixties, but was not much heard outside their jargon until the arbs stared to exploit the gaps between the price of stock index futures and the actual level of the market in the mid eighties. This and the increasing use of program trading brought the term into the daily papers, especially when one of the quarterly triple witching hours was approaching; they occur on the third Friday of the final month of each quarter and involve stock options, stock index options, and stock index futures. Several days before last Friday's 'triple witching hour', many professional stock traders again braced for a wild final 60 minutes in the life of three key market forces...and a wild 60 minutes it was. New York Times 24 June 1985, p. 5 Wall Street also responded to concerted action by the major U.S. financial markets to close down programme trading...which became notorious because of the so-called triple witching hour volatility. Jordan Times 21 Oct. 1987, p. 1