Global InformationKaibun information
Kaibun (Japanese: 回文 or かいぶん, lit. 'circle sentence') is a Japanese equivalent of the palindrome, or in other words, a sentence that reads the same from the beginning to the end or from the end to the beginning. The unit of kaibun is mora, since the Japanese language uses syllabaries, hiragana and katakana.
Single word palindromes are not uncommon in Japanese. For example, Ku-ku (九九, multiplication table), Shi-n-bu-n-shi (新聞紙, newspaper), to-ma-to (トマト, tomato), etc. So kaibun usually refers to a palindromic sentence, but a passage can be a kaibun too.
The topic marker "wa" (は) can be treated as "ha" and small kana ゃ,ゅ and ょ are usually allowed to be interpreted as big kana や, ゆ and よ. In classics, diacritic marks are often ignored.
Rather than saying "read the same forwards and backwards", because Japanese is traditionally written vertically, Japanese people describe the word as being the same when read from the top (ue kara yomu) as when read from the bottom (shita kara yomu).