NA, N.A., Na, nA or n/a may refer to:

Chemistry and physics

Sodium Sodium is a chemical element; it has Symbol (chemistry), symbol Na (from Neo-Latin ) and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 element, group 1 of the peri ...

, symbol Na, a chemical element * Avogadro constant (''N''_A) * Nucleophilic addition, a type of reaction in organic chemistry * Numerical aperture, a number that characterizes a range of angles in an optical system * nA, the symbol for nanoampere * Naturally aspirated engine

Biology and medicine

* Na (tree) or ''Mesua ferrea'', a species of tree native to Sri Lanka * Neuroacanthocytosis, a neurological condition * '' Nomina Anatomica'', a former international standard for human anatomical nomenclature * Noradrenaline, a hormone * Nucleic acid analogue, compounds analogous to naturally occurring RNA and DNA

Places

Current

Namibia Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the no ...

(ISO country code) *

Naples Naples ( ; ; ) is the Regions of Italy, regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 908,082 within the city's administrative limits as of 2025, while its Metropolitan City of N ...

(car number plate code: NA), Italy *

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

, a continent *

North Africa North Africa (sometimes Northern Africa) is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of t ...

, a subcontinent

Historical

* Netherlands Antilles (former international vehicle registration code: NA) * Na (Chinese state), a small state of the Chinese Zhou dynasty from the 11th to 8th centuries BC * Nakoku, or Na, a state in Kyūshū, Japan from the 1st to early 3rd centuries AD

Names and titles

* Na (羅), a Korean surname related to the Chinese surname Luo * Na, a particle used in Thai noble names * National Academician, a member of the National Academy of Design

Art and entertainment

* Na (drum), a drum played by Tibetan shamans * Nahal, Shine's pet Bengal tiger on the Nick Jr. TV show '' Shimmer and Shine'' * New adult fiction, fiction marketed to people 18–30 years old * '' Virgin New Adventures'', a series of ''Doctor Who'' novels * ''Na'' (EP) by Nayeon, 2024

Transport

* NA, the tailcode of VFA-94 * Nepal Airlines, the national flag carrier airline of Nepal * North American Airlines (IATA code: NA) * Naturally aspirated engine * NA MX-5 Miata, the first generation of the Mazda Miata

Language

* Na (cuneiform), a cuneiform sign * Na (Javanese) (ꦤ), a letter in the Javanese script * Na (kana), a Japanese kana * Na dialect, a Sino-Tibetan variety of India * Na language (Narua), a Sino-Tibetan language of Yunnan, China * Nauruan language (ISO code: na)

Organizations

* Narcotics Anonymous (NA), a twelve-step program that focuses on recovery from drug addiction * National Alliance (Latvia), a Latvian political party * National Alliance (Netherlands), a former Dutch political party * National Association (disambiguation) * National Association of Professional Base Ball Players, the first professional baseball league * Nepali Army, the land military force of Nepal * Neurotics Anonymous (N/A), a program for recovery from mental and emotional illness

Other uses

* .na, the top-level domain for Namibia * N/A, meaning not applicable, not available, or no answer * N.A., the official designation of federally chartered banks in the United States * Mosuo or Na, an ethnic group in China near Tibet * Na people, an ethnic group in India * National Archives, the archives of a country