I think it’s the biggest ship, or ‘kind of ship’ that’s built from… well, metal.
Edit: LOL, I genuinely read that as ‘Waterworld’. Several times.
Nope. You right. BANG. Pop-cultural headshot!
But I think I get a ‘non-print’ exclusionary Hail Mary.
I guess if Dyson Spheres count then we really are still thinking small.