Definition:Gravitational Constant

Physical Constant
The constant of proportion $G$ in Newton's Law of Universal Gravitation is a physical constant.

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 known as
The gravitational constant can also be seen referred to as the universal gravitational constant.

Also see
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.