Why the first purpose-built naval ram is hard to identify

Which ironclad was the first ship built with a ram?

The priority claim depends on separating a purpose-built ram from an ordinary or merely ram-strengthened bow, and contemporary descriptions do not always make that boundary clear.

The question first requires a definition of what counts as a ram. A bow might be designed specifically for ramming, strengthened enough to perform the function, or simply built strongly without being described that way. Those categories can overlap in surviving descriptions, so an apparently simple first becomes difficult to prove. Naval-architecture priority claims therefore need a functional definition as well as a ship name or contemporary label. The same method helps when evaluating other disputed technological milestones.