【MSA (消歧义)】
MSA可能指：
==组织或企业==
*马来西亚-新加坡航空：新加坡航空及马来西亚航空的前身。
*交通运输部海事局（China Maritime Safety Administration）
*海上保安厅（旧称Maritime Safety Agency，今称Japan Coast Guard）
*Maritime Security Agency, aka the Pakistan Coast Guard
*Masonic Service Association, a Freemasonry publishing resource
*Microscopy Society of America, a society for the promotion of microscopy
*Mine Safety Appliances, a manufacturer of industrial safety clothing and equipment
*Mineralogical Society of America, an organization for the advancement of mineralogy
*Motion Sensing Alliance, an alliance for the development of motion sensing technology
*Motor Sports Association, the governing body for motorsport in the United Kingdom
*Mutual Security Agency, established by the US Mutual Security Act (1951), and distributed aid to Europe after the Marshall Plan
*Mycological Society of America, a society promoting the study of fungi
==教育==
===学位===
* Master of Accountancy, an accounting degree
* Master of Science in Administration, a degree providing preparation for administrative positions
===学校===
* Mackintosh School of Architecture, an architecture school in Glasgow, Scotland
* Manchester School of Architecture, an architecture school in Manchester, England
* Maryland School of the Arts, a fictional dance school in the film Step Up
* Middle States Association of Colleges and Schools, an evaluation and accreditation association
* Minnesota Math and Science Academy, a school in Minnesota
* Mississippi School of the Arts, a high school in Brookhaven, Mississippi
* Missouri Scholars Academy, a summer program at the University of Missouri
* MSA Mutfak Sanatlari Akademisi, a culinary arts institute in Istanbul, Turkey
* Modern Sciences and Arts University, a university in October City, Egypt
* Monash Student Association, the student government association of Monash University, Melbourne, Australia
* Muslim Students' Association, a group dedicated to Islamic societies on college campuses in Canada and the United States
== 科学及医学 ==
* 5-甲氧基水杨酸（5-Methoxysalicylic acid）：一种化合物，在MALDI质谱中用作基质。
* 甘露醇盐琼脂（Mannitol salt agar）：一种微生物培养基。
* Measurement systems analysis, the analysis of the process of obtaining measurements
* 甲基磺酸（Methanesulfonic acid）
* Middle Stone Age, a period of African prehistory
* 多重序列比对（Multiple sequence alignment）是对三个以上的生物学序列，如蛋白质序列、DNA序列或RNA序列所作的序列比对。
* Multiple system atrophy, a degenerative neurological disorder
* Multiscale approximation 或多解析度分析（multiresolution analysis）
* Morphosyntactic alignment (linguistics)
* Measure of sampling adequacy, a quality criterion for a correlation matrix as prequisition for factor analysis (statistics)
== 科技 ==
* Hewlett Packard Modular Smart Array, the primary storage device for some data centres
* Mail submission agent, a computer program used when sending email
* Master service agreements, a master agreement defining services to be delivered
* Microsoft Access：一种资料库管理系统
* Mobile Service Architecture, a combination of Java ME extensions
* MSA，MIPS SIMD 架构
* Multi-source agreement, an agreement between multiple manufacturers to make products which are compatible across vendors
== 运输 ==
* MSA Garratt, a steam engine class of the Western Australian Government Railways
* 公路服务区（Motorway service area）
* Muskrat Dam Airport, an airport at Muskrat Dam, Ontario, Canada (IATA code)
==其他==
* 马来语（Malay language）
*Mapping Services Agreement, a licensing contract between local authorities in the United Kingdom and suppliers of geographic data
* Matthew Shepard Act, 2009 United States federal hate-crime legislation
*Market Square Arena, an indoor arena in Indianapolis, Indiana demolished in 2001
*Medical savings account, a tax-deferred deposit account for medical expenses
*Metropolitan Statistical Area, a geographical area associated with an urban area of 50,000 people or more, as defined by the United States Office of Management and Budget
*United States Micropolitan Statistical Area, a geographical area associated with an urban area of 10,000 to 49,999 people, as defined by the United States Office of Management and Budget
*Minimum safe altitude, used for safely navigating aircraft over terrain or large structures
*现代标准阿拉伯语（Modern Standard Arabic）
*Tobacco Master Settlement Agreement, an agreement reached between U.S. States and major tobacco companies
*MSA Kyotei, a Japanese abbreviation in reference to U.S. and Japan Mutual Defense Assistance Agreement.
* Minesweeper Auxiliary