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IN THEORY: Light speed is the rate of travel of light in an un-interupted vacuum. Exactly 299,792,458 metres per second (m/s), where metre is difined by 1983 Systeme International (SI) as "The length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second.". The theory of realitivity describes light speed as impassible in rate of travel, but this is based on the fact it hasn't been done yet *rolls eyes*.

However, Light Speed is acctually better told as such: The speed of light is the commonly used interval of time it takes for the green light to turn amber on a traffic light in South Essex, UK, or the time it takes for a traffic warden to travel from the end of the street to the parking spaces to give you a ticket as soon as you pull in.
Light speed is roughly equal to the speed light travels.
by regs_ October 27, 2004

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2
The minigame in rubik's revolution in which you must press the correct light in time
R.R.: Light Speed.
Player: Ok, here we go.
via giphy
by A M80N8R May 27, 2016

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3
Imagine the speed of Superman, that is lightspeed!
by brendan July 01, 2004

### The Urban Dictionary Mug

One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.

4
The speed at which the car in front of you is traveling which assures you'll get caught by the upcoming traffic light.
Passenger: Do you think we'll make it through the upcoming green light before it changes?
Driver: Nope, the idiot in front of me is going light speed.
by Valet Parking Hater January 21, 2015

### The Urban Dictionary Mug

One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.