Warship is the broad category, while battleship originally meant a vessel intended for the battle line. The word described what a ship would do rather than a rigid hull type. As cruiser and destroyer became established labels, battleship likewise hardened into the name for the battle-line branch of a shared ironclad lineage. Early battleships emphasized close, punishing combat, while cruisers tended to be longer so they could maneuver through independent cruising engagements.
Notable Point · 28:42-30:08
Battleship began as a battle-line function
The battleship label originally described a ship's place in the battle line rather than a rigid hull category.