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We are the world's largest and most comprehensive directory and search engine for acronyms, abbreviations and initialisms on the Internet. Abbreviations.com holds hundreds of thousands of entries organized by a large variety of categories from computing and the Web to governmental, medicine and business and it is maintained and expanded by a large community of passionate editors.

Academic & Science

Amateur Radio, Architecture, Biology, Chemistry, Degrees, Electronics, Geology, IEEE, Mathematics, Mechanics, Meteorology, Ocean Science, Physics, Universities»

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Accounting, Firms, International Business, Mortgage, NASDAQ Symbols, NYSE Symbols, Occupations & Positions, Professional Organizations, Stock Exchange, Tax»

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Computing

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Internet

ASCII, Blogs, Chat, Domain Names, Emoticons, HTTP, MIME, Twitter, Wannas, Websites»

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Regional

Airport Codes, African, Alaska, Australian, Canadian, Cities, Countries, Currencies, European, Language Codes, Railroads, Tel. Country Codes, Time Zones, US States»

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OTIS
Online Transportation Information System
OTIS
Online Technology and Instructional Sessions
OTIS
Outstanding Technology Innovative and Service
OTIS
Outside The Inner Sanctum
OTIS
Optical Thermal Imaging System

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