"The World" (as a Capitalized Abstraction) is vague in English. Depending on context, you might say:
- le terdi
- le se terdi
- ro se terdi
- ... and probably plenty more
Other suggestions?
- munje
- remna munje
- cfipyboi
From the jvoste:
- mu'ezda
- rolgu'e
- rolre'azda
- rolzda