Robert Comsol wrote:
Suffice to say I'm inclined to take the Klingon definition in ST III ("Federation Battlecruiser") with grains of salt.
A Constitution-class starship can destroy the entire habitable surface of a planet. I don't think it is a stretch to classify it as a battle cruiser.
The term "battle cruiser" would indicate "a cruiser built for battle" - as our real world battle cruisers were. Since the main mission of the Enterprise
and her sister ships is peaceful exploration, armed only for self-defense, Starfleet would definitely not classify her as a battle cruiser! And that regardless of the firepower she possesses.
How the Klingons designate Starfleet vessels doesn´t necessarily have anything nothing to do with their "real" classifications. The Klingons will have different designations for their vessels, especially since the purpose of the Klingon fleet is obviously battle, war and conquest.