15-letter words containing w, a, f
- towers of hanoi — (games) A classic computer science problem, invented by Edouard Lucas in 1883, often used as an example of recursion. "In the great temple at Benares, says he, beneath the dome which marks the centre of the world, rests a brass plate in which are fixed three diamond needles, each a cubit high and as thick as the body of a bee. On one of these needles, at the creation, God placed sixty-four discs of pure gold, the largest disc resting on the brass plate, and the others getting smaller and smaller up to the top one. This is the Tower of Bramah. Day and night unceasingly the priests transfer the discs from one diamond needle to another according to the fixed and immutable laws of Bramah, which require that the priest on duty must not move more than one disc at a time and that he must place this disc on a needle so that there is no smaller disc below it. When the sixty-four discs shall have been thus transferred from the needle on which at the creation God placed them to one of the other needles, tower, temple, and Brahmins alike will crumble into dust, and with a thunderclap the world will vanish." The recursive solution is: Solve for n-1 discs recursively, then move the remaining largest disc to the free needle. Note that there is also a non-recursive solution: On odd-numbered moves, move the smallest sized disk clockwise. On even-numbered moves, make the single other move which is possible.
- transfer window — the period during the year in which a football club can transfer players from other teams into their own
- wager of battle — (in medieval Britain) a pledge to do battle for a cause, esp to decide guilt or innocence by single combat
- walk-in traffic — The walk-in traffic of a store is the number of people who choose to visit it as they pass by.
- walking catfish — an Asian catfish, Clarias batrachus, that can survive out of water and move overland from one body of water to another: introduced into Florida.
- walnut husk fly — any of several fruit flies, as Rhagoletis completa, the larvae of which feed on and discolor walnut husks.
- warrant officer — (in the U.S. Armed Forces) an officer of one of four grades ranking above enlisted personnel and below commissioned officers.
- waterfall model — (programming) A software life-cycle or product life-cycle model, described by W. W. Royce in 1970, in which development is supposed to proceed linearly through the phases of requirements analysis, design, implementation, testing (validation), integration and maintenance. The Waterfall Model is considered old-fashioned or simplistic by proponents of object-oriented design which often uses the spiral model instead. Earlier phases are sometimes called "upstream" and later ones "downstream". Compare: iterative model.
- waterford glass — fine cut or gilded glass made in Waterford, Ireland, having a slight blue cast due to the presence of cobalt.
- weatherproofing — Present participle of weatherproof.
- week after week — every week or for many successive weeks
- welfare officer — a person who gives people help and advice
- welfare statism — the belief in or practices of a welfare state.
- well-formulated — to express in precise form; state definitely or systematically: He finds it extremely difficult to formulate his new theory.
- white zinfandel — a medium-sweet rosé wine made from zinfandel grapes.
- windfall profit — a profit that arises thanks to an external event over which the person profiting had no control
- witch of agnesi — a plane curve symmetrical about the y- axis and asymptotic to the x- axis, given by the equation x 2 y =4 a 2 (2 a − y).
- wolf-rayet star — a very hot (35,000–100,000 K) and luminous star in the early stages of evolution, with broad emission lines in its spectrum.
- wrongful arrest — the act of arresting someone without proper reason
- yellow goatfish — a schooling goatfish, Mulloidichthys martinicus, inhabiting the Atlantic Ocean from Florida to Panama.