Does Japanese have any infixes? In English, we have prefixes, like "pre-"; suffixes, like "-ize"; and arguably, expletives that function as infixes (one classic example is "abso-fucking-lutely"). In Japanese, we also have prefixes, like , ; and suffixes, like , {}. Does Japanese have any infixes, though? I'm interested both in any modern, productive infixes that may exist that I'm not aware of, as well as any historically-productive infixes that are now fossilized.

To the best of my knowledge there are none. Infixes are really pretty rare crosslinguistically, so it's not that surprising. English's expletive ones are pretty unusual even by English's standards, and as far as I know they're not particularly productive (I can't think of too many words you're actually allowed to use them with).