As you may already know, Japanese has three different alphabets: Katakana, Hiragana, and Kanji. Many words are written in only one of these scripts (ex: カタカナ、ひらがな、漢字), and using a split of Hiragana and Kanji is required when writing verbs (ex: 食べる). However, occasionally one sees a noun also written this way, such as “子ども”. Why not just write it in all Kanji (子供) or all hiragana (こども)? While either of these is correct, seeing the mixed “子ども” is actually not uncommon at all. So why could this be?
There are many reasons Kanji, Hiragana, or Katakana might be used for a specific word, but generally speaking, writing nouns using information-dense Kanji is preferred because of quick readability. For example, “成田空港” (Narita Airport) is a succinct four characters in Kanji but nearly doubles to seven characters when written out in Hiragana (“なりたくうこう”) (Of course for those of us struggling with learning our first few hundred Kanji, we may wish everything was Hiragana, but fear not – things will get easier) There are a few reasons not to use Kanji for nouns, for example:
- The audience is very young and knows little to no Kanji (ex: children’s books)
- The Kanji is advanced or uncommon so that some adults may not know it
- The word is a loanword (パソコン), or a word that describes a sound or sensation (ジャリジャリ), which are commonly written in Katakana (there are others in the category as well)
- The author wants to avoid the stiff feeling that Kanji can invoke (流石）
However, 子ども doesn’t apply to any of the above cases. The reason it is preferred by some people is actually a bit surprising. The second character in “子供”, “供” is part of the word “お供え物”, which means a gift or offering to someone. Supposedly some parents have opposed to using this character to describe their child since “my child is not an offering”, and have complained about it in places like middle school PTA meetings. As a result 子ども is used since it is doesn’t have that connotation. Surely there are some people who would object to this reasoning and prefer the traditional “子供” wait of writing the word.
Let’s look at another case of this mixed-writing.
“障害者” (shougaisha), which means something like “handicapped person”, can sometimes be seen written as “障がい者”. For someone who is used to reading Kanji, this looks quite awkward, especially since the Hiragana is stuck in between two Kanji characters.
Once you understand that the character “害” means “harm”, and is used in words like “害虫” (harmful insect), it’s easy to see why some people might object to “障害者”, since it could be seen as implying “handicapped people are harmful” (or if you read between the lines “a nuisance to society”). This is clearly not true, but on the other hand handicapped people are usually “harmed” in some way by an ailment or accident, so it’s hard to say the character doesn’t fit in some sense. In fact, the root word “障害” means “obstacle, hindrance, or difficulty”, and this can be used as fodder by both sides of the argument, depending on whether you view the “hindurance” as the injury or the person themselves. Like with “子ども”, there are some Japanese people who think its perfectly fine to just use the full Kanji way of writing the word (障害者).
However, if you dig deeper you’ll find there is a bit more to the story. “障害者” was previously written as “障碍者”, with the change to the middle character done because ”碍” was not part of the Toyo Kanji List (当用漢字) which is the predecessor of the more well-known Joyo Kanji List (常用漢字), that contains about ~2000 characters designated for common use. Because “碍” and “害” both have the same sound (“gai”), the former was replaced with the latter (which is part of the official Toyo Kanji List).
At first this seems a good argument for writing the word as “障がい者” or even reverting back to the original “障碍者”, however if you look up the original ”碍” character in a dictionary you’ll find it has a very similar meaning (“hindrance”), so if you ask me this line of reasoning is a bit weak.
My personal feelings is that a completely different word be used, and I have seen some usage of “ハンディキャップ”, coming from the english “Handicap”, although I wonder if this has a stronger connotation of a Sports handicap in Japanese, since it is used for Golf. You may remember that a similar debate occurred in American English with the word “retarted”, which was mostly replaced by “handicapped” in modern day language.
A third word I came across recently was “親戚” (relative) written in mixed script as “親せき”. My gut feeling is that this is because one of the meanings of “戚” is “to be sad” or “lament”, though I haven’t verified that with a native speaker. “戚” is part of the Joyo Kanji List, so it’s not because the character is not well known.
The act of writing one or more characters in a word in Hiragana while retaining at least one Kanji character is called 交ぜ書き（”mazegaki”).
The reason for 親せき is because 戚 is difficult to write or memorize. You seem to care of the Joyo kanji list, but to be honest, ordinary people don’t care of it and not few people don’t know even the existence of the list per se.