

Pure sciences and exact or mathematical sciences, including astronomy, mechanics and mathematical physics.
| Acronym | Sense | Language | Topics | 
|---|---|---|---|
| N | Nitur = N | Azote | In French = N | Stikstof | In Afrikaans = N | نيتروجين | In Arabic = N | Nitróxenu | In Asturian = N | Azot | In Azerbaijani = N | Азот | In Belarusian = N | Азот | In Bulgarian = N | নাইট্রোজেন | In Bengali = N | Dušik | In Bosnian = N | Nitrogen | In Catalan = N | Azotu | In Corsican = N | Dusík | In Czech = N | Азот | In Chuvash = N | Nitrogen | In Welsh = N | Kvælstof | In Danish = N | Stickstoff | In German = N | Άζωτο | In Greek = N | Nitrogen | In English = N | Azoto | In Esperanto = N | Nitrógeno | In Spanish = N | Lämmastik | In Estonian = N | Nitrogeno | In Basque = N | نیتروژن | In Persian = N | Typpi | In Finnish = N | Azôt | In Friulian = N | Nítrigin | In Irish = N | Nitróxeno | In Galician = N | નાઇટ્રોજન | In Gujarati = N | Neetragien | In Manx = N | חנקן | In Hebrew = N | नाइट्रोजन | In Hindi = N | Dušik | In Croatian = N | Azòt | In Haitian Creole = N | Nitrogén | In Hungarian = N | Ազոտ | In Armenian = N | Nitrogeno | In Interlingua = N | Nitrogen | In Indonesian = N | Nitro | In Ido = N | Azoto | In Italian = N | 窒素 | In Japanese = N | trano | In Lojban = N | აზოტი | In Georgian = N | 질소 | In Korean = N | Stickstoff | In Kölsch = N | Nîtrojen | In Kurdish = N | Nitrogenium | In Latin = N | Stéckstoff | In Letzeburgesh = N | Stikstof | In Limburgish = N | Azoti | In Lingala = N | Azotas | In Lithuanian = N | Slāpeklis | In Latvian = N | Hauota | In Māori = N | Азот | In Macedonian = N | നൈട്രജന് | In Malayalam = N | Азот | In Mongolian = N | नायट्रोजन | In Marathi = N | Ehēcatehuiltic | En Nahuatl = N | Stickstoff | In Low German = N | Stikstof | In Dutch = N | Nitrogen | In Nynorsk = N | Nitrogen | In Norwegian = N | Nitrogene | NOV = N | Azòt | In Occitan = N | Nitrogen | In Kapampangan = N | Azot | In Polish = N | Nitrogénio | In Portuguese = N | Qullpachaq | In Quechua = N | Azot | In Romanian = N | Азот | In Russian = N | Azzotu | In Sicilian = N | Dušik | In Serbo-Croatian = N | Dusík | In Slovak = N | Dušik | In Slovenian = N | Azoti | In Albanian = N | Азот | In Serbian = N | Kväve | In Swedish = N | Nitrojeni | In Swahili = N | நைட்ரஜன் | In Tamil = N | నత్రజని | In Telugu = N | Азот | In Tajik = N | ไนโตรเจน | In Thai = N | Azot | In Turkish = N | Азот | In Ukrainian = N | Azot | In Uzbek = N | Nitơ | In Vietnamese = N | 氮 | In Chinese | In Icelandic | → Chemistry | 
| N | Azoto = (look above) | In Italian | → Chemistry | 
| N | 窒素 = (look above) | In Japanese | → Chemistry | 
| N | trano = (look above) | In Lojban | → Chemistry | 
| N | აზოტი = (look above) | In Georgian | → Chemistry | 
| N | 질소 = (look above) | In Korean | → Chemistry | 
| N | Stickstoff = (look above) | In Kölsch | → Chemistry | 
| N | Nîtrojen = (look above) | In Kurdish | → Chemistry | 
| N | Nitrogenium = (look above) | In Latin | → Chemistry | 
| N | Stéckstoff = (look above) | In Letzeburgesh | → Chemistry | 
| N | Stikstof = (look above) | In Limburgish | → Chemistry | 
| N | Azoti = (look above) | In Lingala | → Chemistry | 
| N | Azotas = (look above) | In Lithuanian | → Chemistry | 
| N | Slāpeklis = (look above) | In Latvian | → Chemistry | 
| N | Hauota = (look above) | In Māori | → Chemistry | 
| N | Азот = (look above) | In Macedonian | → Chemistry | 
| N | നൈട്രജന് = (look above) | In Malayalam | → Chemistry | 
| N | Азот = (look above) | In Mongolian | → Chemistry | 
| N | नायट्रोजन = (look above) | In Marathi | → Chemistry | 
| N | Ehēcatehuiltic = (look above) | En Nahuatl | → Chemistry | 
| N | Stickstoff = (look above) | In Low German | → Chemistry | 
| N | Stikstof = (look above) | In Dutch | → Chemistry | 
| N | Nitrogen = (look above) | In Nynorsk | → Chemistry | 
| N | Nitrogen = (look above) | In Norwegian | → Chemistry | 
| N | Nitrogene = (look above) | [NOV] | → Chemistry | 
| N | Azòt = (look above) | In Occitan | → Chemistry | 
| N | Nitrogen = (look above) | In Kapampangan | → Chemistry | 
| N | Azot = (look above) | In Polish | → Chemistry | 
| N | Nitrogénio = (look above) | In Portuguese | → Chemistry | 
| N | Qullpachaq = (look above) | In Quechua | → Chemistry | 
| N | Azot = (look above) | In Romanian | → Chemistry | 
| N | Азот = (look above) | In Russian | → Chemistry | 
| N | Azzotu = (look above) | In Sicilian | → Chemistry | 
| N | Dušik = (look above) | In Serbo-Croatian | → Chemistry | 
| N | Dusík = (look above) | In Slovak | → Chemistry | 
| N | Dušik = (look above) | In Slovenian | → Chemistry | 
| N | Azoti = (look above) | In Albanian | → Chemistry | 
| N | Азот = (look above) | In Serbian | → Chemistry | 
| N | Kväve = (look above) | In Swedish | → Chemistry | 
| N | Nitrojeni = (look above) | In Swahili | → Chemistry | 
| N | நைட்ரஜன் = (look above) | In Tamil | → Chemistry | 
| N | నత్రజని = (look above) | In Telugu | → Chemistry | 
| N | Азот = (look above) | In Tajik | → Chemistry | 
| N | ไนโตรเจน = (look above) | In Thai | → Chemistry | 
| N | Azot = (look above) | In Turkish | → Chemistry | 
| N | Азот = (look above) | In Ukrainian | → Chemistry | 
| N | Azot = (look above) | In Uzbek | → Chemistry | 
| N | Nitơ = (look above) | In Vietnamese | → Chemistry | 
| N | 氮 = (look above) | In Chinese | → Chemistry | 
| N2H2 | Hydrazine | In English | → Chemistry | 
| Na | Sodium = Na | Natrium | In Afrikaans = Na | صوديوم | In Arabic = Na | Sodiu | In Asturian = Na | Натрый | In Belarusian = Na | Натрий | In Bulgarian = Na | সোডিয়াম | In Bengali = Na | Natrijum | In Bosnian = Na | Sodi | In Catalan = Na | Sodiu | In Corsican = Na | Sodík | In Czech = Na | Sodiwm | In Welsh = Na | Natrium | In Danish = Na | Natrium | In German = Na | ސޯޑިއަމް | In Dhivehi = Na | Νάτριο | In Greek = Na | Sodium | In English = Na | Natrio | In Esperanto = Na | Sodio | In Spanish = Na | Naatrium | In Estonian = Na | Sodio | In Basque = Na | سدیم | In Persian = Na | Natrium | In Finnish = Na | Sodi | In Friulian = Na | Sóidiam | In Irish = Na | Sodio | In Galician = Na | Sodjum | In Manx = Na | נתרן | In Hebrew = Na | सोडियम | In Hindi = Na | Natrij | In Croatian = Na | Sodyòm | In Haitian Creole = Na | Nátrium | In Hungarian = Na | Նատրիում | In Armenian = Na | Natrium | In Indonesian = Na | Natro | In Ido = Na | Natrín | In Icelandic = Na | Sodio | In Italian = Na | ナトリウム | In Japanese = Na | sodna | In Lojban = Na | Natrium | JV = Na | ნატრიუმი | In Georgian = Na | ಸೋಡಿಯಮ್ | In Kannada = Na | 나트륨 | In Korean = Na | Natrîyûm | In Kurdish = Na | Natrium | In Latin = Na | Natrium | In Letzeburgesh = Na | Sodu | In Lingala = Na | Natris | In Lithuanian = Na | Nātrijs | In Latvian = Na | Konutai | In Māori = Na | Натриум | In Macedonian = Na | സോഡിയം | In Malayalam = Na | सोडियम | In Marathi = Na | Natrium | In Low German = Na | Natrium | In Dutch = Na | Natrium | In Nynorsk = Na | Natrium | In Norwegian = Na | Natrium | NOV = Na | Sôdgium | In Norman = Na | Sòdi | In Occitan = Na | Sód | In Polish = Na | Sódio | In Portuguese = Na | Natriyu | In Quechua = Na | Sodiu | In Romanian = Na | Натрий | In Russian = Na | Sodiu | In Sicilian = Na | Natrij | In Serbo-Croatian = Na | Sodík | In Slovak = Na | Natrij | In Slovenian = Na | Natriumi | In Albanian = Na | Натријум | In Serbian = Na | Natrium | In Swedish = Na | Natiri | In Swahili = Na | சோடியம் | In Tamil = Na | సోడియమ్ | In Telugu = Na | Натрий | In Tajik = Na | โซเดียม | In Thai = Na | Sodyum | In Turkish = Na | Натрій | In Ukrainian = Na | Natriy | In Uzbek = Na | Natri | In Vietnamese = Na | Sodiom | In Walloon = Na | 钠 | In Chinese | In French | → Chemistry | 
| Na | Natrium = (look above) | In Afrikaans | → Chemistry | 
| Na | صوديوم = (look above) | In Arabic | → Chemistry | 
| Na | Sodiu = (look above) | In Asturian | → Chemistry | 
| Na | Натрый = (look above) | In Belarusian | → Chemistry | 
| Na | Натрий = (look above) | In Bulgarian | → Chemistry | 
| Na | সোডিয়াম = (look above) | In Bengali | → Chemistry | 
| Na | Natrijum = (look above) | In Bosnian | → Chemistry | 
| Na | Sodi = (look above) | In Catalan | → Chemistry | 
| Na | Sodiu = (look above) | In Corsican | → Chemistry | 
| Na | Sodík = (look above) | In Czech | → Chemistry | 
| Na | Sodiwm = (look above) | In Welsh | → Chemistry | 
| Na | Natrium = (look above) | In Danish | → Chemistry | 
| Na | Natrium = (look above) | In German | → Chemistry | 
| Na | ސޯޑިއަމް = (look above) | In Dhivehi | → Chemistry | 
| Na | Νάτριο = (look above) | In Greek | → Chemistry | 
| Na | Sodium = (look above) | In English | → Chemistry | 
| Na | Natrio = (look above) | In Esperanto | → Chemistry | 
| Na | Sodio = (look above) | In Spanish | → Chemistry | 
| Na | Naatrium = (look above) | In Estonian | → Chemistry | 
| Na | Sodio = (look above) | In Basque | → Chemistry | 
| Na | سدیم = (look above) | In Persian | → Chemistry | 
| Na | Natrium = (look above) | In Finnish | → Chemistry | 
| Na | Sodi = (look above) | In Friulian | → Chemistry | 
| Na | Sóidiam = (look above) | In Irish | → Chemistry | 
| Na | Sodio = (look above) | In Galician | → Chemistry | 
| Na | Sodjum = (look above) | In Manx | → Chemistry | 
| Na | נתרן = (look above) | In Hebrew | → Chemistry | 
| Na | सोडियम = (look above) | In Hindi | → Chemistry | 
| Na | Natrij = (look above) | In Croatian | → Chemistry | 
| Na | Sodyòm = (look above) | In Haitian Creole | → Chemistry | 
| Na | Nátrium = (look above) | In Hungarian | → Chemistry | 
| Na | Նատրիում = (look above) | In Armenian | → Chemistry | 
| Na | Natrium = (look above) | In Indonesian | → Chemistry | 
| Na | Natro = (look above) | In Ido | → Chemistry | 
| Na | Natrín = (look above) | In Icelandic | → Chemistry | 
| Na | Sodio = (look above) | In Italian | → Chemistry | 
| Na | ナトリウム = (look above) | In Japanese | → Chemistry | 
| Na | sodna = (look above) | In Lojban | → Chemistry | 
| Na | Natrium = (look above) | [JV] | → Chemistry | 
| Na | ნატრიუმი = (look above) | In Georgian | → Chemistry | 
| Na | ಸೋಡಿಯಮ್ = (look above) | In Kannada | → Chemistry | 
| Na | 나트륨 = (look above) | In Korean | → Chemistry | 
| Na | Natrîyûm = (look above) | In Kurdish | → Chemistry | 
| Na | Natrium = (look above) | In Latin | → Chemistry | 
| Na | Natrium = (look above) | In Letzeburgesh | → Chemistry | 
| Na | Sodu = (look above) | In Lingala | → Chemistry | 
| Na | Natris = (look above) | In Lithuanian | → Chemistry | 
| Na | Nātrijs = (look above) | In Latvian | → Chemistry | 
| Na | Konutai = (look above) | In Māori | → Chemistry | 
| Na | Натриум = (look above) | In Macedonian | → Chemistry | 
| Na | സോഡിയം = (look above) | In Malayalam | → Chemistry | 
| Na | सोडियम = (look above) | In Marathi | → Chemistry | 
| Na | Natrium = (look above) | In Low German | → Chemistry | 
| Na | Natrium = (look above) | In Dutch | → Chemistry | 
| Na | Natrium = (look above) | In Nynorsk | → Chemistry | 
| Na | Natrium = (look above) | In Norwegian | → Chemistry | 
| Na | Natrium = (look above) | [NOV] | → Chemistry | 
| Na | Sôdgium = (look above) | In Norman | → Chemistry | 
| Na | Sòdi = (look above) | In Occitan | → Chemistry | 
| Na | Sód = (look above) | In Polish | → Chemistry | 
| Na | Sódio = (look above) | In Portuguese | → Chemistry | 
| Na | Natriyu = (look above) | In Quechua | → Chemistry | 
| Na | Sodiu = (look above) | In Romanian | → Chemistry | 
| Na | Натрий = (look above) | In Russian | → Chemistry | 
| Na | Sodiu = (look above) | In Sicilian | → Chemistry | 
| Na | Natrij = (look above) | In Serbo-Croatian | → Chemistry | 
| Na | Sodík = (look above) | In Slovak | → Chemistry | 
| Na | Natrij = (look above) | In Slovenian | → Chemistry | 
| Na | Natriumi = (look above) | In Albanian | → Chemistry | 
| Na | Натријум = (look above) | In Serbian | → Chemistry | 
| Na | Natrium = (look above) | In Swedish | → Chemistry | 
| Na | Natiri = (look above) | In Swahili | → Chemistry | 
| Na | சோடியம் = (look above) | In Tamil | → Chemistry | 
| Na | సోడియమ్ = (look above) | In Telugu | → Chemistry | 
| Na | Натрий = (look above) | In Tajik | → Chemistry | 
| Na | โซเดียม = (look above) | In Thai | → Chemistry | 
| Na | Sodyum = (look above) | In Turkish | → Chemistry | 
| Na | Натрій = (look above) | In Ukrainian | → Chemistry | 
| Na | Natriy = (look above) | In Uzbek | → Chemistry | 
| Na | Natri = (look above) | In Vietnamese | → Chemistry | 
| Na | Sodiom = (look above) | In Walloon | → Chemistry | 
| Na | 钠 = (look above) | In Chinese | → Chemistry | 
| NAA | 1-Naphthylacetic Acid | In English | → Biochemistry, biophysics | 
| NAAEE | National American Association of Environmental Education (www.naaee.org) | In English | → Associations → Education → Threats to the environment → United States | 
| NAAL | North American Aerodynamic Laboratory | In English | → Research institutes → Aerodynamics | 
| NABR | National Association for Biomedical Research (www.nabr.org) | In English | → Associations → Biological sciences → Medicine | 
| NABT | National Association of Biology Teachers (www.nabt.org) | In English | → Associations → Education → Biological sciences | 
| NACEC | North American Commission for Environmental Cooperation (www.cec.org) = CCAAN | Comisión para la Cooperación Ambiental de América del Norte | In Spanish = CNACE | Commission Nord-Américaine de Coopération Environnementale | In French = CNACA | Comissão Norte-americana de Cooperação Ambiental | In Portuguese | In English | → International relations → Environmental protection | 
| NAD | Nicotinamide Adenine Dinucleotide | In English | → Genetics → Biochemistry, biophysics | 
| NAEC | Naval Air Engineering Center | In English | → Aerodynamics → Aeronautics, aircraft | 
| NAIA | National Animal Interest Alliance (www.naiaonline.org) | In English | → Organizations and associations → 5023 | 
| NAM | North American Mesoscale (Model) | In English | → Meteorology, climatology | 
| NAMS | North American Micropaleontology Section | In English | → Organizations and associations → Palaeontology | 
| NANA | Acide N-acétylneuraminique = NeuAc | Acide N-acétylneuraminique | In French | In French | → Biochemistry, biophysics | 
| NAO | North Atlantic Oscillation | In English | → Meteorology, climatology | 
| NAOJ | National Astronomical Observatory of Japan (https://www.nao.ac.jp/) | In English | → Observatories → Japan | 
| NAOMI | North American OpenMath Initiative | In English | → Computer science → Mathematics | 
| NapCo | Osservatorio Astronomico di Capodimonte Napoli - Contributi Astronomici | In Italian | → Serial publications, periodicals → Astronomy | 
| NAR | Nucleic Acids Research | In English | → Serial publications, periodicals → Biochemistry, biophysics | 
| NARME | Natural Resources Management and Ecological Engineering | In English | → Threats to the environment → Ecology | 
| NARR | North American Regional Reanalysis | In English | → Meteorology, climatology | 
| NAS | Numerical Aerodynamic Simulation | In English | → Computer simulation → Aerodynamics | 
| NAS | National Academy of Sciences | In English | → Academies | 
| NASA | National Aeronautics and Space Administration (www.nasa.gov) | In English | → Central administration → Astronomy → Aeronautics, aircraft → Astronautics → United States | 
| NASAC | NASA Conference Publication | In English | → Serial publications, periodicals → Astronomy → Astronautics → United States | 
| NASAL | NASA Circular Letter | In English | → Serial publications, periodicals → Astronomy → Astronautics → United States | 
| NASAR | NASA Reference Publication | In English | → Serial publications, periodicals → Astronomy → Astronautics → United States | 
| NASAS | NASA Special Publication | In English | → Serial publications, periodicals → Astronomy → Astronautics → United States | 
| NASDA | National Space Development Agency | In English | → Central administration → Astronomy → Astronautics | 
| NASM | National Air and Space Museum (www.nasm.si.edu) | In English | → Museums → Astronomy → Aeronautics, aircraft → Astronautics → United States | 
| NASO | North American Space Operations | In English | → Astronomy → Astronautics | 
| NASOH | North American Society for Oceanic History | In English | → Organizations and associations → Marine research, oceanography → History | 
| NATF | Naval Air Test Facility | In English | → Aerodynamics → Aeronautics, aircraft | 
| NatH | Natural History | In English | → Serial publications, periodicals → Biological sciences | 
| NATi | Nordisk Astronomisk Tidsskrift | In Norwegian | → Serial publications, periodicals → Astronomy | 
| NATMA | Nonlinear Analysis Theory Methods Applications | In English | → Serial publications, periodicals → Analysis | 
| NatPh | Nature Physics | In English | → Serial publications, periodicals | 
| Natur | Nature | In English | → Serial publications, periodicals | 
| NAZ | Nachrichtenblatt der Astronomischen Zentralstelle Heidelberg | In German | → Serial publications, periodicals → Astronomy | 
| NBDL | Naval Bio-Dynamics Laboratory | In English | → Research institutes → Biological sciences | 
| NBN | (Asocio por la enkonduko de) Nova Biologia Nomenklaturo | In Esperanto | → Associations → Biological sciences | 
| NBRP | National BioResource Project | In English | → Biological sciences | 
| NC | Neuroscience Center | In English | |
| NCAM | Neural Cell Adhesion Molecule | In English | → Biochemistry, biophysics | 
| nCaR | Nicotinic Acetylcholine Receptor | In English | → Biochemistry, biophysics | 
| NCAR | National Center for Atmospheric Research (www.ncar.ucar.edu) | In English | → Research institutes → Meteorology, climatology | 
| NCIMB | National Collections of Industrial, Marine and Food Bacteria (www.ncimb.com) | In English | → Biological sciences → Food technology | 
| NCimL | Lettere al Nuovo Cimento della Società Italiana di Fisica | In Italian | → Serial publications, periodicals → Physics → Italia | 
| NCM | National Cryptologic Museum (www.nsa.gov/museum/) | In English | → Museums → Computer science → Mathematics | 
| NCOS | National Commission On Space | In English | → Astronomy → Astronautics | 
| NCRR | National Center for Research Resources (www.ncrr.nih.gov) | In English | → Research institutes → Biological sciences → Medicine | 
| ND | NASA Document | In English | → Astronomy → Astronautics → United States | 
| NDGPS | Nationwide Differential Global Positioning System | In English | → Geodesy, cartography → Astronautics → Telecommunications | 
| NDS | Nuclear Data Sheets | In English | → Serial publications, periodicals → Nuclei → Nuclear technology | 
| NEAF | North East Astronomy Forum | In English | → Astronomy | 
| NEAF | National Environmental Advisory Forum | In English | → Organizations and associations → Environmental protection | 
| NEBROC | NEtherlands BRemen OCeanography | In English | → Marine research, oceanography | 
| NEC | North Equatorial Current | In English | → Meteorology, climatology | 
| NEEDS | NASA End-To-End Data System | In English | → Data → Astronomy → Astronautics → United States | 
| NEIC | National Earthquake Information Center (http://earthquake.usgs.gov) | In English | → Organizations and associations → Seismology, earthquakes | 
| NEMURO | North Pacific Ecosystem Model for Understanding Regional Oceanography | In English | → Threats to the environment → Marine research, oceanography | 
| NEON | National Ecological Observatory Network | In English | → Ecology | 
| NEPA | National Environmental Policy Act | In English | → Politics → Environmental science | 
| NERC | Natural Environment Research Council (www.nerc.ac.uk) | In English | → Organizations and associations → Threats to the environment → United Kingdom | 
| NES | Network Encryption System | In English | → Networks, communication → Mathematics | 
| NESDIS | National Environmental Satellite Data and Information Service | In English | → Environmental protection → Astronautics | 
| NESS | National Environmental Satellite Service | In English | → Threats to the environment → Astronautics | 
| NeuAc | Acide N-acétylneuraminique = NANA (look above) | In French | → Biochemistry, biophysics | 
| NewAR | New Astronomy Review | In English | → Serial publications, periodicals → Astronomy |