ALTHOUGH ABBREVIATED forms have been a part of the English language for centuries, the proliferation of words collectively known as acronyms is relatively recent. Acronym, which first entered a dictionary in 1943, means the result of joining together the initial letters or parts of a compound term to produce a new expression that is treated as a single, pronounceable word. It is this quality of pronounceability that distinguishes an acronym from an initialism, the latter consisting entirely of a combination of initials that is usually spoken or read letter by letter. With its lexicographical birth date recorded as 1899, initialism is just a few decades older than acronym, both terms having been previously subsumed under the general heading of abbreviations. Acronyms can refer equally to people, places, and things. One early example of a personal acronym was Rashi, for the medieval Jewish commentator on the Bible and the Talmud, whose full name was Rabbi Shlomo Yitzhaqi. Kenora, in northern Ontario, was born in 1905 by the merger of the first two letters of its three constituent communities: Keewatin, Norman, and Rat Portage. While most acronyms relating to organizations have appeared since the Second World War, ANZAC (Australian and New Zealand Army Corps) dates back to the Gallipoli campaign of 1915. When the titles of institutions are reduced to acronymic form, they may or may not retain their capitalization, as in UNESCO and Inco. Commercial acronyms, such as the computer programs COBOL (Common Business Oriented Language) and FORTRAN (Formula Translation), may also take an optional lower case. Some acronyms become so widespread that they eventually develop into common nouns and tend to lose all trace of their parent words. Snafu (the bowdlerized version of which is situation normal, all fouled up); scuba (self-contained underwater breathing apparatus); laser (light amplification by stimulated emission of radiation); and modem (modulator demodulator) are typical. Government and non-government organizations are a fruitful source of initialisms and acronyms, and in some instances the line between the two different forms may be hard to draw. While the Social Sciences and Humanities Research Council of Canada confers undoubted benefits on non-fiction authors through its financial grants, the attempted pronunciation of its abbreviation SSHRCC could create a wrong impression. Similarly, the acronym MYOP (Multi-Year Operational Plan) sounds inappropriately shortsighted for what is meant to be a federal government`s long-range forecast. The title of the volunteer agency CESO (Canadian Executive Service Organization) is usually pronounced with a hard c, except in Latin America, where the first letter is kept soft to avoid any confusion with queso, the Spanish word for cheese. Because of their increasing popularity, acronyms are often chosen for their anticipated impact, and then expanded into suitable words. This reverse process, or "bacronym" as it has been called, gave rise to such organizations as MADD (Mothers Against Drunk Drivers) and REAL (Realistic, Equal, Active, for Life) Women of Canada. Even more contrived are CRAP (Constructive Republican Alternative Programs), which referred to legislative position papers during the Lyndon Johnson administration, and SEX (Summer Experiment Group), a work opportunity for engineering undergraduates. Occasionally, the artificial acronym carries an intended message so closely resembling the meaning of an existing word that the abbreviated original is not readily apparent. A good illustration is zip (Zone Improvement Plan) code, which suggests a more efficient, presumably speedier, mail delivery. Words of unknown or uncertain origin are sometimes falsely attributed to acronyms. Posh, in the sense of stylish or first-rate, is frequently but dubiously thought to come from "port out, starboard home," in the belief that wealthy English passengers travelling between Britain and the Far East during the colonial era occupied the more expensive cabins on the shaded side of the ship. Another discredited notion concerns the derivation of pommy, a name used in Australia to describe English immigrants, either in a derogatory manner or as an expression of affectionate abuse. One popular theory, unsupported by firm evidence, is that the word is abbreviated from POME (Prisoner of Mother England), in historical allusion to the convicts transported to the Australian penal colony in the 19th century. Wog, an offensive racial slur applied particularly to persons of Arabic or East Indian extraction, is perhaps a contraction of golliwog, but it is also claimed by some writers to be the acronym of Wily Oriental Gentleman. There is even an improbable suggestion that the word is merely a harmless shorthand that was once employed by British military and civil authorities in foreign posts to identify locally recruited personnel as WOGS (Working on Government Service). Regardless of their source or application, acronyms are always written without intervening punctuation. Well, that`s not quite true. Mobile Army Surgical Hospital, a veteran of the Korean War, lives on in television reruns under its unaccount ably asterisked title "M*A*S*H. " And surely the Canadian Centre of P.E.N., the international writers` society, could become mightier than the sword if it would only drop those tiresome, unnecessary periods.