MSR

• Macrophage scavenger receptor, a receptor found in macrophages • Magnetic stripe reader, a device used to read magnetic stripe cards such as credit cards • M–sigma relation, in astrophysics • Mars sample return mission, a spaceflight mission to return rock and dust samples collected on Mars • Mirror self-recognition, in animals through the mirror test • Molten-salt reactor, an advanced nuclear reactor design Computing • Machine state register, a register used in PowerPC architectures • Model-specific register, a feature in x86 processors • Microsoft Reserved Partition, a space-management partition on a computer storage device • Mining software repositories, a field that analyzes the rich data available in software repositories ==Entertainment==

• MSR Studios, a New York recording studio • The Most Serene Republic, a Canadian indie rock band • Metropolis Street Racer, a Dreamcast racing game • Mid-season replacement, a television series that premieres in the second half of a traditional season • Metroid: Samus Returns, a video game • Mulder Scully Romance, the relationship of the main characters of the television series The X-Files • March, Strathspey and Reel, common bagpipe tune set • Monster Studio Records, The in-house music studio for Arknights • Metal Scar Radio, The in-house music studio for Arknights: Endfield ==Organizations and companies==

• Market Street Railway (nonprofit), a historic preservation organization in San Francisco, California, U.S. • Microsoft Research, the research division of Microsoft • Mountain Safety Research, a US company specializing in outdoor equipment • Mouvement social révolutionnaire, the French fascist party Revolutionary Social Movement • Movimiento Social Republicano, the Republican Social Movement political party in Spain • MSR – The Israel Center for Medical Simulation, Israeli institute for Simulation-Based Medical Education ==Places==

• Misamis Oriental (ISO sub-national code), a province in the Philippines • Most Serene Republic, a title in the name of various countries • Montserrat (ISO 3166-1 code) ==Transportation==

• EgyptAir (ICAO designator), an Egyptian airline • Main supply route, a military operations supply route • Market Street Railway (transit operator), a defunct company in California, US • Michigan Shore Railroad, US • Muar State Railway, a defunct railway formerly operating in Malaya (now Malaysia) • Mumbai Suburban Railway, India • Muş Airport (IATA airport code), Turkey ==Weapons==

• Modern sporting rifle or AR-15 style rifle • Modular Sniper Rifle, a sniper rifle produced by Remington Arms • Magnum Sniper Rifle or Accuracy International Arctic Warfare, a bolt-action sniper rifle ==Other uses==

• Market Stability Reserve, a part of the European Union Emissions Trading System • Milan–San Remo, an annual bicycle race • Mortgage servicing rights, the rights to collect mortgage payments from a borrower for the benefit of the lender • Meyer Shank Racing, an American auto racing team