C9, C09 or C-9 may refer to:

Biology, medicine, and chemistry

* C9 ( Complement component 9), a protein *

ATC code C09 C09A ACE inhibitors, plain C09AA ACE inhibitors, plain :C09AA01 Captopril :C09AA02 Enalapril :C09AA03 Lisinopril :C09AA04 Perindopril :C09AA05 Ramipril :C09AA06 Quinapril :C09AA07 Benazepril :C09AA08 Cilazapril :C09AA09 Fosinopril :C09AA10 Trando ...

, a subgroup of the Anatomical Therapeutic Chemical Classification System * C09, ICD-10 code for malignant neoplasm of tonsil * Carbon-9 (C-9 or ⁹C), an isotope of carbon

Military and weapons

* Hi-Point

Models C9 and C9 Comp The Hi-Point Model C-9 is a polymer-framed, semi-automatic, blowback-operated pistol manufactured by Hi-Point Firearms. It is chambered in 9×19mm Parabellum and is rated to accept +P ammunition. It became well known for its low retail price of ...

handguns *

C9 LMG The FN Minimi (short for french: Mini Mitrailleuse; "mini machine gun") is a Belgian 5.56mm light machine gun/squad automatic weapon developed by Ernest Vervier for FN Herstal. First introduced in the late 1970s, it is now in service in more tha ...

, Canadian light machine gun * C9, an ID for the German ''Nachtjagdgeschwader'' 5 air squadron in World War II

Music

* C9, a note five octaves above

Middle C C or Do is the first note and semitone of the C major scale, the third note of the A minor scale (the relative minor of C major), and the fourth note (G, A, B, C) of the Guidonian hand, commonly pitched around 261.63 Hz. The actual frequen ...

* C9, a C ninth chord

Organizations

* Cloud9, an American esports organization *

C9 League The C9 League () is an alliance of nine universities in China, initiated by the Government of China, Chinese Central Government to promote the development and reputation of higher education in China in 2009. Collectively, universities in the C9 ...

, an association of Chinese universities * The Council of Cardinal Advisers, an advisory body to the pope, originally comprising nine members * C9 Entertainment, a South Korean entertainment company and record label

Transportation

Cierva C.9 __NOTOC__ The Cierva C.9 was an experimental autogyro built by Cierva in England in 1927, in association with Avro AVRO, short for Algemene Vereniging Radio Omroep ("General Association of Radio Broadcasting"), was a Dutch public broadcas ...

, a 1927 British experimental autogyro * HMS ''C9'', a British submarine *

Ford C-9 The Ford Trimotor (also called the "Tri-Motor", and nicknamed the "Tin Goose") is an American three-engined transport aircraft. Production started in 1925 by the companies of Henry Ford and ended on June 7, 1933, after 199 had been made. It w ...

, a US military designation for the Ford Trimotor aircraft * McDonnell Douglas C-9, a US Air Force transport aircraft based on the civilian DC-9 * USS ''Montgomery'' (C-9), a US Navy cruiser * C9, the IATA code for Cirrus Airlines * Sauber C9, a Le Mans racing car * C9 engine, by Caterpillar Inc. *

C-9 (Cercanías Madrid) Line C-9, formerly known as the Guadarrama Electric Railway ( es, Ferrocarril Eléctrico del Guadarrama), is a narrow-gauge mountain railway incorporated into Madrid's Cercanías commuter rail network. The line is operated by Renfe Operadora an ...

, a commuter rail line in Madrid

Other uses

* C9, an

ISO 216 ISO 216 is an international standard for paper sizes, used around the world except in North America and parts of Latin America. The standard defines the "A", "B" and "C" series of paper sizes, including A4, the most commonly available paper size ...