異世界（いせかい、isekaい）
- another world

The Japanese word 異世界, pronounced いせかい (isekai), translates to "another world," "different world," or "alternate world." It refers to a fictional setting that is distinct from the real world. This other world can be of various types: a fantasy realm, a science fiction universe, a historical period, or even a parallel version of our own world. The concept of 異世界 often involves a protagonist, usually a human from the real world, being transported or reincarnated into this different reality.

⚫︎そのアニメは異世界を舞台にしています。 Translation: That anime is set in another world. ⚫︎彼はトラックにひかれて異世界に転生した。 Translation: He was hit by a truck and reincarnated into another world. ⚫︎このゲームは、プレイヤーが異世界を探検する内容です。 Translation: This game involves players exploring another world.

⚫︎You can use 異世界 when discussing stories, movies, anime, manga, and games that involve the concept of a different world. ⚫︎It's common to use it to describe the setting or the overall genre of the media. ⚫︎You can use it to talk about the plot of the story or even the specific features of the different world.

⚫︎The word 異世界 is typically written with the kanji 異 (i - different/strange), and 世界 (sekai - world). ⚫︎The reading is いせかい (isekai) in hiragana. ⚫︎There are no variations in okurigana (suffix hiragana).

⚫︎There aren't many direct synonyms for 異世界, as the term is quite specific. However, words like "alternate universe" or "parallel world" could be used to convey a similar meaning in English.

⚫︎The direct antonym would be something like 現実世界 (genjitsu sekai - the real world) or この世界 (kono sekai - this world).

最近、異世界をテーマにした小説が人気です。 ・Translation: Novels with the theme of another world are popular recently. ・Explanation: This sentence describes the popularity of stories with the 異世界 theme.

彼女は異世界もののラノベが大好きです。 ・Translation: She loves light novels about other worlds. ・Explanation: This sentence explains someone's preference for light novels dealing with the concept of 異世界.

The word 異世界 is a compound word formed from 異 (i - different/strange) and 世界 (sekai - world). The combination directly indicates "a different world" or "a strange world".