J (disambiguation)

Look up J or j in Wiktionary, the free dictionary.

J is the tenth letter of the Latin alphabet.

J may also refer to:

Astronomy

J, a provisional designation prefix for some objects discovered between May 1 and 15 of a year

J (programming language), successor to APL
J# programming language for the Microsoft .NET Framework
J (text editor), written in Java
J operator, a programming construct
J (operating system), an operating system for ICL's System 4 series of computers

Haplogroup J (mtDNA)
Haplogroup J (Y-DNA)
ATC code J Antiinfectives for systemic use, a section of the Anatomical Therapeutic Chemical Classification System

J, symbol used to denote the Bessel function
j, used as the symbol for the imaginary unit ( $\sqrt{-1}$ ) in fields where i is used for a different purpose (such as electrical current)
j, the second imaginary unit of a quaternion
$j$ , an index variable in a matrix
The j-invariant, a modular function

Joule, the SI unit of energy (represented by capital letter J, in upright (non-slanted) type)
J, the SI-recommended dimension symbol for luminous intensity, conventionally rendered in a sans-serif typeface
Current density
Second moment of area
J, name given by Samuel C. C. Ting for the J/ψ particle
J-coupling, indirect dipole-dipole coupling between two nuclear spins

"J", song by Reggie and the Full Effect from the album Last Stop: Crappy Town
"J", song by Mindless Self Indulgence from the album Frankenstein Girls Will Seem Strangely Sexy

J, slang for joint (cannabis)
J, slang for Air Jordan shoes
J, slang for a jump shot in basketball
J band, radio frequencies ranges from 10 to 20 GHz
J (psychedelic), an entactogenic drug
J (New York City Subway service)
J Church, a light rail line in San Francisco
Elgin, Joliet and Eastern Railway, a Chicago railway sometimes referred to as "The J"
J, the international license plate code for Japan
J, the Canadian postal code for the western and northern regions of Quebec
J, German mint mark for the city of Hamburg
J abbreviation for Jahwist, one of the major authors of the Torah
J, an abbreviated title of a High Court judge (in Law Reports, etc.), e.g. Bloggs J
j., a weekly newspaper serving the Jewish community in Northern California
J, the narrator of Jerome K. Jerome's novel Three Men in a Boat
J., Jezper Söderlund, the trance artist
Lamborghini Aventador J, a 2012 Lamborghini supercar
J (novel), a 2014 novel by Howard Jacobson