USS Einstein wrote:
I guess there is no on-screen evidence to support our belief however.
For all we know 'D7' was a Starfleet designation, and 'KTinga' was the Klingon name for the same ship.
To be fair, the names for most vessel designs come from offscreen material.
Also, the term Battlecruiser and Warbird now seem to be interchangeable for Klingon ships.
Probably not too unlike how the terms heavy cruiser and starship may be interchangeable for some Federation ships.
The D7/K'tinga design does have a somewhat bird-like appearance, but if we go with the idea that the Klingons and the Romulans once were allies and shared & swapped stuff during TOS, the term "warbird" may have originated with the Klingons anyway.