Why is C the symbol for the speed of light? (2004)

[Physics FAQ] - [Copyright] By Philip Gibbs, 1997, 2004. Why is c the symbol for the speed of light? "As for c, that is the speed of light in vacuum, and if you ask why c, the answer is that it is the initial letter of celeritas, the Latin word meaning speed." Isaac Asimov in "C for Celeritas (1959)" [1] A Short Answer Weber apparently meant c to stand for "constant" in his force law, but there is evidence that physicists such as Lorentz and Einstein were accustomed to a common convention that c could be used as a variable for velocity. This usage can be traced back to the classic Latin texts in which c stood for "celeritas" meaning "speed". The uncommon English word "celerity" is still used when referring to the speed of wave propagation in fluids. The same Latin root is found in more familiar words such as acceleration and even celebrity, a word used when fame comes quickly. Although the c symbol was adapted from Weber's constant, it was probably thought appropriate f ... Read full article.