B (disambiguation)

B is the second letter of the Latin alphabet.

B may also refer to:

Astronomy

 * Astronomical objects in the Barnard list of dark nebulae (abbreviation B)
 * Latitude (b) in the galactic coordinate system

Biology and medicine

 * Haplogroup B (mtDNA), a human mitochondrial DNA (mtDNA) haplogroup
 * Haplogroup B (Y-DNA), a Y-chromosomal DNA (Y-DNA) haplogroup
 * Blood type B
 * ATC code B Blood and blood forming organs, a section of the Anatomical Therapeutic Chemical Classification System
 * Vitamin B
 * Hepatitis B
 * Berlin Botanical Garden and Botanical Museum, assigned the abbreviation B as a repository of herbarium specimens

Computing

 * B (programming language)
 * B-Method, for computer software development
 * B-tree, a data structure
 * Bit (b)
 * Byte (B)
 * , an HTML element denoting bold text

Physical and chemical quantities and units

 * One of the reciprocal lattice vectors (b*)
 * Breadth (b); see length
 * Impact parameter (b)
 * Molality (b)
 * Barn (unit) (b), a unit of area
 * Magnetic field (B)
 * Napierian absorbance (B)
 * Rotational constant (B)
 * Second virial coefficient (B)
 * Susceptance (B)
 * Bel (B), a logarithmic unit equal to ten decibels

Other uses in science, technology, and mathematics

 * B, a modal logic
 * bottom quark (symbol: b), an elementary particle
 * B meson, a type of meson
 * Boolean domain ($$\mathbb{B}$$), in mathematics
 * Boron, symbol B, a chemical element
 * Bulb (photography), a shutter-speed setting
 * B battery, a battery used to provide the plate voltage of a vacuum tube
 * B horizon, a layer of soil commonly known as subsoil
 * B, B+ and B−, expressions of buoyancy in convective available potential energy

Linguistics

 * В, a letter of the Cyrillic alphabet
 * Voiced bilabial stop (b, in the International Phonetic Alphabet)

Musical notation

 * B (musical note)
 * B major, a scale
 * B minor, a scale
 * B major chord, Chord names and symbols (popular music)
 * ♭ Flat (music), a note lower in pitch by a semitone

Performers

 * Beyoncé
 * B, member of Superorganism (band)

Recordings

 * B (BamBam EP), an extended play by BamBam
 * B (Battles EP), an extended play by Battles
 * B (I Am Kloot album), a compilation album by I Am Kloot
 * b (Moxy Früvous EP), an extended play by Moxy Früvous
 * "b", an Iamamiwhoami song
 * "B", a song by Todrick Hall from his 2018 album Forbidden

Other media

 * /b/, a board on 4chan
 * b (newspaper), a free daily, tabloid sized newspaper, published by The Baltimore Sun
 * Codex Vaticanus Graecus 1209, an ancient bible
 * Rajawali Televisi, previously named B Channel, a television channel in Indonesia
 * B, the production code for the 1963–64 Doctor Who serial The Daleks
 * B, a character in Total Drama: Revenge of the Island
 * "B" Is for Burglar, the second novel in Sue Grafton's "Alphabet mystery" series, published in 1985

Places

 * Belgium, on the vehicle registration plates of the European Union
 * Bucharest, on the vehicle registration plates of Romania

Sport

 * Australian rules football positions, in Australian Rules football
 * B, often used after the name of football clubs to denote a reserve team

Transportation

 * B (New York City Subway service)
 * B Line (Los Angeles Metro)
 * Line B (Buenos Aires Metro)
 * B (S-train), in Copenhagen
 * RER B, a line in the RER of Paris
 * The West Japan Railway Company service symbol for:
 * Kosei Line
 * Inbi Line
 * Kabe Line
 * Bundesstraße (federal highway) in Austria and Germany (abbreviation B)
 * Bayshore Route of Shuto Expressway in Japan, numbered as route B

Other uses

 * B (grade), for evaluation of students' work
 * B (bank), a banking brand in the United Kingdom
 * Barnabites (Clerici Regulares Sancti Pauli), a religious order abbreviated to the postnominal B.
 * Bravo, the military time zone code for UTC+02:00
 * Brutus, a Roman cognomen (abbreviation B)
 * Farmall B, a tractor produced by International Harvester from 1939 to 1947
 * Dominical letter B for a common year starting on Saturday
 * B, a soft grade of pencil lead