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c

c

9 7.7
The speed that light travels in empty space, exactly 299,792,458 meters per second
  • noun
  • Specialized
translation icon : c
  • "According to Captain LoCarno, we went from point-nine-nine c to practically zero in a matter of minutes."
  • the speed of light, c
  • light, c

Now I chose C for a reason, because it's the speed of light.

Examples

  • Hint: the answer is always (c) and will always be (c).

    Blog text (6)
  • So this is somehow some kind of very special luminosity, in the same way that C is a very special speed.

  • So this speed C is an invariant speed.

  • The ratio of energy to momentum for a light beam is equal to the speed of light, c.

    Academic text (2000)
  • According to special relativity, a normal object cannot reach the speed of light in a vacuum, c.

    Academic text (1996)
  • The two new transformations apply for relative velocities between c and infinity (not including either).

    Blog text (2)
  • The speed of light, represented by c, is approximately 299,792,458 meters per second.

  • In physics, c is the constant that defines the maximum speed at which all massless particles travel.

  • When discussing relativity, it's important to remember that nothing can exceed the speed of c.

Synonyms

speed of light
vsc
  • Specialized
43 3.8

A constant speed at which light travels in empty space, about 300,000 kilometres per second

is the scientific symbol naming that exact physical constant
light speed
vsc
  • Specialized
8 5.0

The speed that light travels in empty space

is the scientific symbol used instead of the spelled-out phrase
lightspeed
vsc
  • Specialized
2 4.9

The fastest speed at which light moves in empty space

is the scientific symbol for the exact numerical value rather than general claim

Compounds

C-section
  • Specialized
41 3.4

A surgery to deliver a baby by making cuts in the mother's abdomen and womb

vitamin C
  • Specialized
30 1.1

A substance in fruits and vegetables that helps the body stay healthy and fight illness

hepatitis C
  • Specialized
15 3.8

A liver infection caused by a virus spread through blood, for example by sharing needles

2 3.5

A major key with no sharps or flats that uses only the white keys on a piano

D and C
  • Specialized
1 8.0

A surgery that opens the cervix and removes tissue from the womb

middle C
  • Specialized
1 4.2

The note C near the center of a piano used as a reference in music

C compiler
  • Specialized
1 4.7

A computer program that turns C code into instructions the computer can run

C program
  • Specialized
1 3.4

A computer program written in the C language

C-reactive protein
  • Specialized
1 4.3

A protein made by the liver that rises in the blood as a sign of infection or inflammation

C and W
  • US
4.0

A style of popular music from the southern United States with guitars and songs about everyday life

C battery
  • Archaic
8.1

A small cell that gives steady voltage to set the grid of an old radio tube

C clef
  • Specialized
9.8

A movable sign on a music staff that shows middle C

C flute
  • Specialized
4.0

A common concert wind instrument played by blowing across a hole tuned to C and used in orchestras

C horizon
  • Specialized
8.1

A soil layer below the B layer and above bedrock made of partly broken rock with little plant material

A sequence of notes C D E F G A B with no sharps or flats

6.5

A metal clamp shaped like a C that holds wood or metal firmly while you work

chlorophyll c
  • Specialized
6.5

A green pigment in brown algae and tiny water organisms that helps make food from light

C-horizon
  • Specialized
9.6

A soil layer under the B-horizon and above bedrock made mostly of broken rock with few plant roots

C-ration
  • Archaic
9.3

A canned meal given to American soldiers during wars

cytochrome c
  • Specialized
5.5

A small protein in mitochondria that helps move energy in cells

scale of C major
  • Specialized
3.7

A set of notes from C to B with no sharps or flats

the c-word
  • Offensive
9.9

An indirect way to say a very offensive word for a woman's private parts

Surface Forms

c singular
cs plural

Etymology

C comes from the Latin word celeritas, which means 'swiftness' or 'speed'. So when scientists use c for light, it reminds us that light has an always-the-same speed in empty space.