Not sure about TPs/Turbofans but piston engines have designator codes. Here's a brief summary:
O - Horizontally opposed
I- Fuel Injection
T - Turbocharged
G - Geared
S - Supercharged
Can't think of any others... anyone care to add?
The number after the letters is the engine's displacement in Cubic Inches (to convert to Cubic Centimeters multiply by 16.4). The number/letter after that specifies what magnetos are used, I think.
So, for example, an IO-360-L2A engine is a horizontally-opposed, fuel-injected engine with a displacement of 360ci (about 5900cc) equipped with L2A magnetos.
Anyone care to explain the coding system used for turbines?
Smithy.