Definition:Universal Gravitational Constant

Physical Constant
The universal gravitational constant is the physical constant which is the constant of proportion in Newton's Law of Universal Gravitation.

Its value in SI units is referred to as $G$ and is approximately equal to $6.674 \times 10^{-11} \, \mathrm N \, \mathrm m^2 \, \mathrm{kg}^{-2}$.

Also see

 * Definition:Local Gravitational Constant

Gravitational Constant: $G = 6.67 \times 10^{-8} \, \mathrm{cm}^{-3} \, \mathrm{gm}^{-1} \, \mathrm{sec}^{-2}$ is a track by on their $1991$ album. It is about committing suicide.

As well it might be. If I'd had to express the physical constants in CGS units when I'd been in college, I doubt I'd have found a reason to stay alive myself.