L2

L2, L², L02, L II, L.2 or L-2 may refer to:

Astronomy

• L₂ point, second Lagrangian point in a two body orbiting system
• L₂ Puppis, star which is also known as HD 56096
• Advanced Telescope for High Energy Astrophysics, a proposed X-ray telescope

Biology

• Haplogroup L2 (mtDNA) in human genetics
• ATC code L02 Endocrine therapy, a subgroup of the Anatomical Therapeutic Chemical Classification System
• the second lumbar vertebrae of the vertebral column in human anatomy
• the second larval stage in the Caenorhabditis elegans worm development

Computing

• L2 cache, the Level-2 CPU cache in a computer
• Layer 2 of the OSI model, in computer networking
• L2 (operating system), or Liedtke 2 (a.k.a. EUMEL/ELAN), a persistent microkernel operating system developed by German computer scientist Jochen Liedtke
• L2 (programming language)
• ISO/IEC 8859-2 (Latin-2), an 8-bit character encoding

Entertainment

• L2 (music group), an American pop duo
• L2: Empuraan, a 2025 Indian film, also called L2E
  • L2: Empuraan (soundtrack), soundtrack album to L2: Empuraan
• Leprechaun 2, a 1994 American film
• Lineage II, a 2003 MMO game
• Lumines II, a 2006 puzzle game
• L2, a former name of the O2 Academy Liverpool

Mathematics

• The L² space of square-integrable functions
• L² norm
• The ℓ² space of square-summable sequences
• L² cohomology, a cohomology theory for smooth non-compact manifolds with Riemannian metric
• L₂(n), the family of 2-dimensional projective special linear groups on finite fields.
• Ridge regression, regression and regularization method also known as L2 regularization

Technology and weapons

• a variety of low-alloy special purpose steel
• a L-carrier cable system developed by AT&T
• a series of fragmentation hand grenades used by the British armed forces (American M61 copies), before being replaced by the L109 grenade
• the L designation given to the Sterling submachine gun in the British armed forces
• a frequency used in GPS satellite navigation signals, see GPS signals, a newer version is the L2C frequency

Transportation

Aircraft

• LZ 18 (L 2), a short-lived 1913 German airship (Imperial Navy designation: L 2)
• Arado L II, a 1929 German model of high-wing sporting monoplane
• ASJA L2, a pair of 1932 Swedish trainer biplanes
• Lawson L-2, a 1920 American biplane airliner
• Macchi L.2, an Italian model of biplane flying boat
• L-2 Grasshopper, an American Taylorcraft model used in WWII
• PZL Ł.2, a 1929 Polish model of liaison aircraft

Aviation

• Junkers L2, an engine model; precursor to the Junkers L5
• Lynden Air Cargo, Alaskan airline (IATA code: L2)
• Walker County Airport (or Bevill Field), Alabama, U.S. (former FAA LID: L02)

Rail locomotives

• Chesapeake and Ohio Class L-2 and L-2a, an American 4-6-4 "Hudson" type steam locomotives model
• Milwaukee Road class L2, an American 2-8-2 "Mikado" type steam locomotive
• SP&S Class L-2, an 1881 steam locomotives class
• LNER Class L2, a 1925 class of 2-6-4Ts

Other modes of transport

• L2 (New York City bus), a temporary bus route in New York City, U.S.
• The Randwick branch of the CBD and South East Light Rail in Sydney, Australia, numbered L2
• L2, an S-Bahn line of the Léman Express in Switzerland and France

Other uses

• Second language (L2), a non-native, acquired tongue of an individual
• L², a Flemish political youth organization
• L-2 visa, a U.S. travel document for dependents of temporary workers
• a class of FM radio broadcasting in North America
• Ligue 2, a French association football league
• L2 Inc, an American market research company

See also

• 2L (disambiguation)
• LII (disambiguation)
• Level 2 (disambiguation)