Mauritania country code

Mental retardation, a developmental disorder

Marathi language (ISO 639-1)

Midland Railway

Relative molecular mass

Maximum Ride, a book about human-avian hybrids by James Patterson

Mitral regurgitation, leaking of the mitral valve of the heart

Magnetic resonance

Mineralocorticoid receptor

Master of the Rolls, in the UK legal system

Mahinda Rajapaksa, President of Sri Lanka

McCune-Reischauer, a system of romanization for the Korean language

Magyar Rádió, a Hungarian radio station

Mouvement Réformateur, a Belgian political party

MR layout

Master Replicas, a maker of prop replicas

Mathematical Reviews, a database of reviews of mathematics publications

Mountain Rescue

Air Mauritania

Marina and Rainer (1989), one-act chamber opera by Nikolai Korndorf

Market Researcher, an occupation

Morgoth's Ring, a book by Christopher Tolkien

Magnetoresistance is the property of a material to change the value of its electrical resistance when an external magnetic field is applied to it. The effect was first discovered by William Thomson (more commonly known as Lord Kelvin) in 1856, but he...

Mileage run, a paid/revenue airline trip designed solely for gaining maximum frequent flyer miles and/or points

Marginal Revenue, an economics term

Mr., an honorific title of men, see also Master (form of address). MR. may also refer to:

Menntaskólinn í Reykjavík, a secondary school in Iceland