Why is 明日 pronounced あした?

[Xosen]

Hi!
So I thought that when two kanji where together, they usually used their on-yomi reading. And that is more or less true, since one possible reading, although rarely used, is みょうにち.
So from where do come the あした and あす readings?
Cheers!

 

[Toritoribe]

That's called 熟字訓[じゅくじくん].

Kanji - Wikipedia, the free encyclopedia

 

[Xosen]

Ok, so there are some words that have their own pronunciation that have nothing to do with the sounds of the individual kanji.

That was really useful, thanks!

 

[Toritoribe]

It's not "some" but "quite so many", though.

熟字訓 - Wikipedia

 

[FinancialWar]

Tell me if I am wrong.

I think it is called ateji Ateji - Wikipedia, the free encyclopedia

ASHITA is Japanese word for tomorrow, because the Japanese already have a word for tomorrow, there is no need to import this word from China however, the written form is still desired, hence they give 明日 the pronunciation ASHITA, and eliminate the Onyomi.

 

[Toritoribe]

See explanations on wiki.

In modern Japanese, ateji (当て字, 宛字 or あてじ, literally "assigned characters") primarily refers to kanji used phonetically to represent native or borrowed words, without regard to the meaning of the underlying characters.

The term ateji is also used for the opposite process, writing words using kanji for meaning only, without regard to the reading.

For example, sushi is often written with the ateji 寿司. Though the two characters are respectively read as su and shi, the character 寿 means "one's natural life span" and 司 means "to administer", neither of which has anything to do with the food.

An example of the opposite process (meaning only) is 煙草 (tabako) for "tobacco", where the individual kanji respectively mean "smoke" and "herb" but have no phonetic relationship to the word tabako. This is also considered a kind of ateji.

Jukujikun can be considered a form of ateji.

Thus, 明日 is a jukujikun, and at the same time, an ateji in the broad sense of the term.