**Rule of three** — Rule Rule, n. [OE. reule, riule, OF. riule, reule, F. r[ e]gle, fr. L. regula a ruler, rule, model, fr. regere, rectum, to lead straight, to direct. See {Right}, a., and cf. {Regular}.] 1. That which is prescribed or laid down as a guide for… … The Collaborative International Dictionary of English

**Rule of three** — Three Three, n. 1. The number greater by a unit than two; three units or objects. [1913 Webster] 2. A symbol representing three units, as 3 or iii. [1913 Webster] {Rule of three}. (Arith.) See under {Rule}, n. [1913 Webster] [1913 Webster] … The Collaborative International Dictionary of English

**rule of three** — n. Math. the method of finding the fourth term of a proportion when three terms are given: the product of the first and last terms is equal to the product of the second and third … English World dictionary

**rule of three** — a rule in mathematics: the product of the means in a proportion equals the product of the extremes used for finding the fourth term of a proportion where three are given * * * Math. the method of finding the fourth term in a proportion when three … Useful english dictionary

**Rule of three (programming)** — Rule of three is a code Refactoring rule of thumb to decide when a replicated piece of code should be replaced by a new procedure. It states that you are allowed to copy and paste the code once, but that when the same code is replicated three… … Wikipedia

**Rule of Three (play)** — Rule of Three is a set of three one act plays by British author and playwright Agatha Christie. It was first published in 1963. The three plays are entitled The Rats , Afternoon at the Seaside , and The Patient … Wikipedia

**Rule of three (writing)** — For other uses, see Rule of Three. The Three Bears The rule of three is a principle in writing that suggests that things that come in threes are inherently funnier, more satisfying, or more effective than other numbers of things. The… … Wikipedia

**Rule of Three (Wiccan)** — The Rule of Three (also threefold law or law of return) is a tenet of the Neopagan religion of Wicca. It claims that whatever energy a person puts out into the world, be it positive or negative, will be returned to that person three times.… … Wikipedia

**Rule of three (C++ programming)** — The rule of three (also known as the Law of The Big Three or The Big Three) is a rule of thumb in C++ that claims that if a class or struct defines one of the following it should probably explicitly define all threecite book last = Stroustrup… … Wikipedia

**Rule of three (medicine)** — The rule of three states that, if no major adverse events occurred in a clinical trial of a drug, then there can be 95% confidence that major adverse events do not happen more often than one in n/3 people, where n is the number of people in the… … Wikipedia