ESR may refer to:
Organizations Earlham School of Religion, at Earlham College in Richmond, Indiana, US E.S.R., Inc., a former American toy manufacturer ESR Rīga, a Soviet Latvian football club, active from 1966 to 1991 ESR Technology, a UK company e-Shang Redwood, an Asia focused Real Estate services and investment firm (), the Greek National Council for Radio and Television European Society of Radiology Institute of Environmental Science and Research, a New Zealand scientific institute
Science EISCAT Svalbard radar, UHF-band radar at Longyearbyen, Norway Electron spin resonance, a technique used in chemical spectroscopy to identify unpaired electrons and free radicals Electron spin resonance dating, a dating technique used in archaeology and geology Erythrocyte sedimentation rate, the rate at which red blood cells sediment Estrogen receptor, a group of proteins European Sociological Review, sociological scientific journal
Technology Electro-slag remelting, an alloy remelting and refining process Electronic Staff Record, a human resources and payroll system of the UK National Health Service Equivalent series resistance, the resistive parts of the impedance of certain electrical components Emergency sun reacquisition, an attitude control mode of the Solar and Heliospheric Observatory Extended-support release, software that receives official security updates for an extended period of time M2010 Enhanced Sniper Rifle, a sniper rifle used by the US Army
Transportation East Somerset Railway, a heritage railway in the UK Eastar Jet (ICAO code), a Korean airline Eastern Suburbs Railway, a railway line in Sydney, New South Wales, Australia Ricardo García Posada Airport (IATA code), Chile Emergency speed restriction, a UK railway speed reduction
Other uses Eric S. Raymond (born 1957), American computer programmer, author and open source software advocate Emile Smith Rowe, English professional footballer for Fulham FC Effort Sharing Regulation, a European Union policy on greenhouse gas emissions