for Informatics and Mathematics ERI – (s) Eritrea (ISO 3166 trigram) ERLAWS – (a) Eastern Ruapehu Lahar Alarm and Warning System ERN – (s) Eritrean nakfa (ISO 4217 currency code) EROS – (a) Earth Resources Observation System ERP – (i) Engineer Regulating Point ERR – (p) Eesti Rahvusringhääling ERS – (i) Earth Resources Survey ERTS – (i) Earth Resources Technology Satellite (became Landsat) ERV – (p) Endogenous RetroVirus ES es – (s) Spanish language (ISO 639-1 code) Es (s) Einsteinium Exasecond ES (s) El Salvador (FIPS 10-4 country code) (i) Electronic warfare Support (s) Exasiemens Spain (ISO 3166 digram; from the country's native name of España) ESA (i) Electro-Spark Alloying Endangered Species Act European Space Agency ESC (i) Embryonic Stem Cell Electronic Stability Control ESD – (i) ElectroStatic Discharge ESDP – (i) European Security and Defence Policy ESE – (i) East South-East ESH – (s) Western Sahara (ISO 3166 trigram) ESL – (i) English as a Second Language ESM – (i) Electronic warfare Support Measures ESO – (i) European Southern Observatory ESOL – (a) English for Speakers of Other Languages ESP (i) Electronic Stability Program Extra-sensory perception (s) Spain (ISO 3166 trigram) ESPGHAN - European Society for Paediatric Gastroenterology, Hepatology and Nutrition ESPN – (i) Entertainment and Sports Programming Network est – (s) Estonian language (ISO 639-2 code) EST (i) Eastern Standard Time (UTC−5 hours) (s) Estonia (ISO 3166 trigram) ESU – (i) Emergency Services Unit ESV – (i) Engineer Support Vehicle ET et – (s) Estonian language (ISO 639-1 code) ET (s) Ethiopia (ISO 3166 digram; FIPS 10-4 country code) Exatesla (i) Extra Terrestrial ETA (i) Estimated Time of Arrival (a) Euzkadi Ta Azkatasuna ("etta", Basque, "Basque Homeland and Freedom") et al. – (p) et alii/aliae/alia (Latin, "and others") ETB – (s) Ethiopian Birr (ISO 4217 currency code) ETC/RMT – (i) Explosive Transient Camera/Rapidly Moving Telescope Etc. - Et cetera ETF – (i) Emergency Task Force (a special police unit, also jocularly said to stand for Extra-Thick Fuzz) ETH – (s) Ethiopia (ISO 3166 trigram) ETI – (i) Extra-Terrestrial Intelligence ETK (i) Easy Tool Kit (i) Embedded Tool Kit Ersatzteikatalog (German: spare parts catalog) ETLA – (i) Extended TLA ETM (i) Electronic Technical Manual (i) Enhanced Thematic Mapper ETOPS - (a) Extended-range Twin-engine Operational Performance Standards (aviation) et seq. – (p) et sequens/sequentes/sequentia (Latin, "and the following one(s)") ETT – (i) Embedded Training Team EU eu – (s) Basque