N3

N3 may refer to:

Roads

N3-class battleship, a Royal Navy battleship design that was never built
USS N-3 (SS-55), a 1915 coastal defense submarine of the US Navy
SP&S Class N-3, a steam locomotives class from the Spokane, Portland and Seattle Locomotive Roster
N₃, gauges for monitoring a third section in a triple spool jet engine
N3, IATA code for the Russian airline Omskavia
N3, European large goods vehicles above 12 tonnes
N3 Pup - the Preceptor N3 Pup ultralight aircraft (and derivatives)

Haplogroup N (Y-DNA), a former human Y-chromosomal haplogroup, now N1c
n-3, Omega-3 fatty acid
Trinitrogen (N₃), inorganic molecule composed of three nitrogen atoms
N−3, an azide anion in chemistry
N³⁻, a nitride anion in chemistry
N3 Lung cancer, metastasis to certain lymph nodes
N₃, the genus three non orientable surface
N3, cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)ruthenium(II), a red dye in dye-sensitized solar cells
N3, abbreviation for the 3 nanometer process node in semiconductor technology

N3 (Calgary), condominium building
N3 (NHS), the national broadband network for the English National Health Service
Notation3, or N3 rules, a textual notation for the Resource Description Framework
N3, the third level of the Japanese-Language Proficiency Test
N3, the most recent version of the Nagravision conditional access system for cable and satellite television
N3, a postcode district in the N postcode area in London
N3, the former name of NDR Fernsehen, a German television channel