Noun
(uncountable) A subgenre of the fantasy or science fiction genres that involves the discovery of an unknown world out of time, place, or both.
Used other than figuratively or idiomatically: see lost, world.
Source: en.wiktionary.orgWhat I wanted to do was to get that sense of being in touch with this lost world while holding onto what draws readers and audiences there in the first place. Stephen Greenblatt
When I was a child, I wanted to... go into space! To go to Mars. I wanted to explore and explore and explore. I wanted to go to the Lost World in South America - I was heartbroken to discover there were no dinosaurs; I still don't accept it. Brian Blessed
Fear may very well be a caveman fear of the predator, of the giant lizard chasing them - maybe that's what Steven Spielberg connects with so well in Lost World. Oliver Stone
I suppose there's a melancholy tone at the back of the American mind, a sense of something lost. And it's the lost world of Thomas Jefferson. It is the lost sense of innocence that we could live with a very minimal state, with a vast sense of space in which to work out freedom. George Will
I've become quite a serious explorer: I've been to Everest three times; I'm the oldest man to reach the North Pole; and I've just been to the lost world of Venezuela. Brian Blessed
His work on The Lost World (1925) is well known, but he is most admired for his work on King Kong (1933), a milestone of his films made possible by stop motion animation. Source: Internet