HMS Invincible and the Battlecruiser

The battlecruiser was a type of warship poised dangerously between the true battleship and the cruiser. They carried the big guns of the battleship, but without the armour needed to take on similarly armed ships.
HMS Invincible was the name ship of the Invincible class of battlecruisers, despite being laid down and completed last of the three. She was one of three British battlecruisers sunk at the battle of Jutland.