noun
the world; society; the universe
Broadest sense: the entire physical world, human society, or the universe as a whole.
世界にはたくさんの国がある。
There are many countries in the world.
世界の平和を願う
I wish for world peace.
noun
A particular social or professional realm, such as the art world or business world.
彼は芸術の世界で有名だ。
He is famous in the art world.
ビジネスの世界は厳しい。
The business world is tough.
noun which may take the genitive case particle 'no'
world-renowned; world-famous
Used as a no-adjective in compounds like 世界的 (worldwide) or 世界一 (best in the world).
彼は世界的に有名な科学者だ。
He is a world-famous scientist.
この店のラーメンは世界一おいしいと思う。
I think this shop's ramen is the best in the world.
noun
Buddhist realm; space
Buddhist term: a realm or world system governed by a single Buddha. Original meaning of the word.
仏教では、一つの世界は一人の仏が教化する領域とされる。
In Buddhism, one world is considered the realm where a single Buddha teaches.