The Origins Of "c" As The Speed Of Light Constant

An in depth examination of the convention of using the letter "c" to represent the speed of light is found here.

In the same vein, it is worth observing that the origins of the word "quark" and the specific letters for the quarks (u, d, s, c, b, and t) is much better known and that in the case of the c and b quarks that the letter have represented more than one word. For example, the b quark has been described as both a "bottom quark" (the current mainstream designation) and a "beauty quark."