Look up c1 in Wiktionary, the free dictionary.
C1, C01, C.I or C-1 may refer to:
Arts and media
- C1, a note-octave in music
- C1 Television, a Mongolian television channel
- Schecter C-1 Hellraiser FR, a guitar model
- A Yamaha grand piano model
- "C1", a slang expression in the video game Counter-Strike, used to express agreement
Biology and medicine
Anatomy
- Cervical vertebra 1, the first cervical vertebrae of the vertebral column
- Cervical spinal nerve 1, a spinal nerve of the cervical segment
Biochemistry
- C1 complex, the first component of the classical complement pathway
- C1 domain, an important secondary messenger protein domain
- C1-inhibitor, a human serine protease inhibitor
- C1 regulatory sequence for the insulin gene
- Apolipoprotein C1, a human lipoprotein
- Chlorophyll c1, a form of chlorophyll
- Cytochrome C1, a precursor protein to Cytochrome C
- Proanthocyanidin C1, a type of polyphenolic compound
- Prostaglandin C1, a form of prostaglandins
Other uses in biology and medicine
- C1 and P1 (neuroscience), a component of the visual evoked potential
- ATC code C01, a subgroup of the Anatomical Therapeutic Chemical Classification System
- C01, the ICD-10 code for "malignant neoplasm of base of tongue", a form of oral cancer
- C1, the short name for a microfluidic single-cell analysis system sold by Fluidigm
Chemistry
- C1 Chemistry, study of methane, methanol, carbon monoxide, carbon dioxide
Computing
Hardware
- C-One, a single-board microcomputer
- C1 NES TV, a family of Nintendo-television-set hybrids manufactured by Sharp Corporation in 1983
- ATI C1, codename of the Xbox 360 GPU Xenos
Other uses in computing
- C0 and C1 control codes defined in ISO 6429
- C1 (protocol), a 1984 protocol for file transfer, also known as "Punter"
- TCSEC C1 security class
- A CPU power state in the Advanced Configuration and Power Interface
Mathematics
, the set of all continuously differentiable functions
- C1 field, a quasi-algebraically closed field
- C1, the first of four pure modules taken in the Advanced Level (UK) Maths syllabus
Transportation
Air
- C-1 Trader, a cargo-version of the S-2 Tracker anti-submarine warfare aircraft of the United States Navy
- AEG C.I, a German World War I reconnaissance aircraft
- AGO C.I, a 1915 German reconnaissance biplane
- Albatros C.I, a 1915 German two-seat general-purpose biplane
- Aviatik C.I, a 1915 German observation plane
- Cierva C.1, a 1920 Spanish experimental autogyro
- DFW C.I, a WWI German reconnaissance aircraft
- Douglas C-1, a cargo/transport airplane produced by Douglas Aircraft for the U.S. Army Air Service starting in 1925
- Fokker C.I, a 1918 German reconnaissance biplane
- Friedrichshafen C.I, a 1914 German single-engined amphibious reconnaissance biplane
- Hansa-Brandenburg C.I, a 1916 German 2-seater armed single-engine reconnaissance biplane
- Kawasaki C-1, an indigenous transport aircraft of the Japanese Air Self-Defense Forces
- Otto C.I, a 1915 German reconnaissance biplane
- Rumpler C.I, a 1915 German two-seater single-engine reconnaissance biplane
- Southern Cross Airport (New Jersey) (FAA LID: C01)
Land
Routes
- Circumferential Road 1 or C-1, an arterial road of Manila, Philippines
- London Buses route C1
- Route C1 (Shuto Expressway), the Inner Loop of Tokyo's Shuto Expressway system
- Claro M. Recto Avenue, a road in Metro Manila, Philippines
- Massachusetts State Route C1
Land vehicles
- BMW C1, a cabin scooter
- Chevrolet Corvette C1, first generation sold from 1953 to 1962, denoted a solid-axle rear-end
- Citroën C1, a small car
- Ford C1 platform, the Ford Motor Company's global compact car automobile platform
- Leapmotor C01, a battery electric executive sedan
- Lit C-1, a prototype cabin motorcycle
- Nimrod NRA/C1, a 1981 test design racing car
- Sauber C1, a Sauber sport car
Other uses in land transport
- C-1, the numberplate of the Prime Minister of Australia's official VIP transportation
- A type of heavy goods vehicle licence
- A one-way traffic sign in the Vienna Convention on Road Signs and Signals
Rail
- Bavarian C I, an 1847 German steam locomotives class
- GNR Class C1 (small boiler), a British 4-4-2 steam locomotive class (classified C2 during LNER ownership)
- GNR Class C1 (large boiler), a British 4-4-2 steam locomotive class
- LB&SCR C1 class, an 1882 British freight steam locomotive
- Long Island Rail Road C1, a bilevel railcar built by Tokyu Car Corporation
- NER Class C1, a British 0-6-0 steam locomotive class
- PRR C1, an American PRR steam locomotive
- Finnish Steam Locomotive Class C1
Sea
- HMS C1, a C-class submarine of the Royal Navy
- USS C-1 (SS-9), a C-class submarine of the United States Navy
- USS Newark (C-1), a protected cruiser of the United States Navy
- Type C1 ship, a small cargo vessel built by the United States in large numbers before and during World War II
- Isaac Peral (C-1), a Spanish submarine
Space
- Cluster 1, also known as Rumba, an ESA satellite
Sports
- C1, a solo canoe discipline including sprint canoe and canoe slalom
- C1 (classification), a para-cycling classification
- C1, an abbreviation for Class One offshore powerboat racing
- 'C1', the top category in Group C sportscar racing, used between 1985 and 1990
- C1, the UEFA Champions League (formerly known as the European Cup) in football
- Serie C1, the third highest football league in Italy until 2008
Other uses
- C1, an international standard paper size defined in ISO 216 (648×917 mm)
- Bills C-1 and S-1, a pro forma bill normally introduced at the start of a parliamentary session in the Canadian House of Commons
- C1, also known as Vlakplaas, a unit of the South African Police responsible for assassinating opponents of Apartheid during the 1980s
- C1, a level in the Common European Framework of Reference for Languages
- C1, the use class for hotels, in town and country planning in the United Kingdom
- C1, a NRS social grade in the United Kingdom for the lower middle class
- a 2001 1.3 megapixels Olympus digital camera model
- a class of FM radio broadcasting in North America
- C1 pylon, a type of high voltage pylon
- Caldwell 1 (NGC 188), an open cluster in Cepheus
- C-1 visa, a type of visa for individuals transiting through the United States
- C1 Espresso, café in Christchurch, New Zealand