L1, L01, L.1, L 1 or L-1 may refer to:

Mathematics, science and technology

Math

  • L<sub>1</sub> distance in mathematics, used in taxicab geometry
  • L<sup>1</sup>, the space of Lebesgue integrable functions
  • ℓ<sup>1</sup>, the space of absolutely convergent sequences
  • Lasso (statistics), a means of regression analysis used in statistics and machine learning

Science

  • L1 family, a protein family of cell adhesion molecules
  • L1 (protein), a cell adhesion molecule
  • L1 or LINE1; transposable elements in the DNA
  • , Lagrangian point 1, the most intuitive position for an object to be gravitationally stationary relative to two larger objects (such as a satellite with respect to the Earth and Moon)
  • Anthranilic acid, also called vitamin L1
  • The first lumbar vertebra of the vertebral column in human anatomy
  • The first larval stage in the Caenorhabditis elegans worm development

Technology

  • L1, one of the frequencies used by GPS systems (see GPS frequencies)
  • L1, the common name for the Soviet space effort known formally as Soyuz 7K-L1, designed to launch men from the Earth to circle the Moon without going into lunar orbit
  • ISO/IEC 8859-1 (Latin-1), an 8-bit character encoding
  • An L-carrier cable system developed by AT&T
  • The level-1 CPU cache in a computer
  • Sony Xperia L1, an Android smartphone
  • A class of FM broadcast station in North America

Transportation and military

  • Lehrgeschwader 1, from its historic Geschwaderkennung code with the Luftwaffe in World War II
  • Lufthansa Systems' IATA code
  • Lawrance L-1, a predecessor of the 1920s American Lawrance J-1 aircraft engine
  • L1 Dulwich Hill Line on the Inner West Light Rail, a light rail service in Sydney, Australia
  • L1 (New York City bus), a temporary bus route in New York City
  • Volkswagen L1, a Volkswagen concept hybrid car
  • L1A1 Self-Loading Rifle
  • L1, an S-Bahn line of the Léman Express in Switzerland and France

Locomotives

  • Erie L-1, an American 0-8-8-0 steam locomotive class
  • GCR Class 1B, latterly known as LNER Class L1, a class of British 2-6-4T steam locomotives
  • GNR Class L1, latterly known as LNER Class R1, a class of British 0-8-2T steam locomotives
  • LNER Thompson Class L1, a class of British 2-6-4T steam locomotives
  • NCC Class L1, a Northern Counties Committee 0-6-0 class steam locomotive
  • Pennsylvania Railroad class L1s, an American 2-8-2 steam locomotive class
  • Soo Line L-1 class, an American 2-8-2 steam locomotive class
  • SP&S Class L-1, an American 4-4-0 steam locomotive class
  • SR L1 class, a class of 4-4-0 steam locomotives of Great Britain
  • VR Class Vr1 (originally L1), a Finnish steam locomotive class

Aircraft

  • Arado L 1, a 1929 German two-seat parasol-wing sporting monoplane
  • Macchi L.1, a 1915 Austro-Hungarian reconnaissance flying boat
  • Stinson L-1 Vigilant, the US Army Air Forces designation for the Stinson Model 74 observation aircraft

Submarines

  • USS L-1 (SS-40), a 1915 United States Navy L-class submarine
  • HMS L1, a Royal Navy submarine

Other

  • Ligue 1, the top division of French football
  • Lowest unique bid
  • L1, in linguistics, a subject's first language or mother tongue
  • L-1 Identity Solutions, a US face-recognition corporation
  • L-1 visa, a document used to enter the United States for the purpose of work
  • L1, an abbreviation denoting someone is a Level 1 Judge, in reference to Magic: The Gathering
  • Bose L1 Portable Systems
  • L=1, a lunar eclipse classification on the Danjon scale
  • L1, the postcode for central Liverpool, a major UK city
  • L1 or Lucifer (2019 Indian film), a 2019 Indian political action thriller film, followed by L2: Empuraan
  • L1 (broadcaster), the public broadcaster for the Dutch province Limburg

;Containing L1

  • ATC code L01 Antineoplastic agents, a subgroup of the Anatomical Therapeutic Chemical Classification System
  • Barcelona Metro line 1
  • DSC-L1, a 2004 Sony Cyber-shot L series camera model
  • Haplogroup L1 (mtDNA), a human mitochondrial haplogroup from Africa
  • Luxo L-1, a lamp
  • Panasonic Lumix DMC-L1, a 2006 single-lens reflex camera

See also

  • Level 1 (disambiguation)
  • 1L (disambiguation)