For instance, the character for east, 東, has the On'yomi tō, from Middle Chinese tung.
Some kanji were introduced from different
parts of China at different times, and so have multiple On'yomi, and often multiple meanings.
Likewise, 明日("tomorrow") is jukujikun, and read neither as akari(no)hi, the kun'yomi of the characters, nor meinichi, the On'yomi of the characters,
Although they are not typically considered jūbako or yutō,
they often contain mixtures of kun'yomi, On'yomi and nanori, such as 大助 Daisuke, 夏美 Natsumi.
Old Japanese scripts often stated that On'yomi readings were also created by the Japanese during their arrival
and re-borrowed by the Chinese as their own.
The On'yomi(音読み, literally"sound(-based)
reading"), the Sino-Japanese reading, is the modern descendant of the Japanese approximation of the base Chinese pronunciation of the character at the time it was introduced.
When it is necessary to distinguish between native Japanese kun'yomi and Chinese-derived On'yomi pronunciations, for example in kanji dictionaries,
the Japanese pronunciations are written in hiragana, and the Chinese pronunciations are written in katakana.