subworld

noun

sub·​world ˈsəb-ˌwər(-ə)ld 

variants or sub-world

plural subworlds or sub-worlds

: a world that is part of a larger world

This season, the show created a whole new subworld within its already intricate and immersive world by taking things under the sea.

—Kayla Kumari Upadhyaya

Word History

First Known Use

1887, in the meaning defined above