I've heard it thrown about in different contexts, but I never quite under neither what it does or what dictates when the sound changes to じゅう in a context, as in 世界中. Anyone have any ideas?
See: japanese.stackexchange.com/questions/2790– nkjtJul 9, 2013 at 7:16
weblio.jp/content/%E4%B8%AD is a good place to look if you can read it– ssbJul 9, 2013 at 14:49
1The part of the question about sound changes is a duplicate but the other part about "what it does" (how 中 on the end of a word is used) isn't thoroughly covered in the linked question. Part 2, 1-4, of the definition here dictionary.goo.ne.jp/leaf/jn2/142924/m1u/%E4%B8%AD could be helpful in answering.– RobinJul 9, 2013 at 17:02
中 roughly means "the space inside". In case of 世界中, it means "the space inside the world", which is "everywhere in the world". In case of 絶望中, it means the person is within the time of despair (it probably helps if you imagine time to be long tube or something).