Ryakuji are not covered in the Kanji Kentei, nor are they officially recognized. However, some abbreviated forms of hyōgaiji included in the JIS standards which conform to the shinjitai simplifications are included in Level pre-1 and above of the Kanji Kentei, as well as some other allowances for alternate ways of writing radicals and alternate forms. Some ryakuji were adopted as shinjitai. Some simplifications are commonly used as special Japanese typographic symbols. These include:
, shime, simplification of as cursive form of top component, used for various kanji read as shime, primarily, also,,, and original ;
, small ke, simplification of , though with other uses.
Of these, only for and for are generally recognized as being simplifications of kanji characters. Replacements of complex characters by simpler standard characters is instead a different phenomenon, kakikae. For example, in writing as , is replaced by the component and is replaced by, in both cases with the same pronunciation but different meanings. The replacement of by is a graphic simplification, while and are graphically unrelated, but in both cases this is simply considered a replacement character, not a simplified form. Other examples include simplifying shōyu to. Compare this to simplified Chinese.
Use
Ryakuji are primarily used in individual memos, notes and other such forms of handwriting. Their use has declined in recent years, possibly due to the emergence of computer technology and advanced input methods that allow equally fast input of both simple and complex characters. Despite this, the ryakuji for and for characters using the radical :ja:門部|門 are still widely used in handwriting.
Abbreviations for multiple-character words or phrases
In all cases discussed in the other sections of this article, individual characters are simplified, but separate characters are not merged. There are rare cases of single-character abbreviations for multiple-character words or phrases, such as for toshokan, "library", but this is very unusual; see polysyllabic Chinese characters for this phenomenon in Chinese, where it is more common.
Examples
Further examples
Omitting components is a general principle, and the resulting character is often not a standard character, as in. If the resulting character is a standard character with the same reading, this is properly kakikae instead, but if it is simply a graphic simplification or the resulting character is not standard, this is ryakuji. One of the most common examples is for haba "width". Often the result would be ambiguous in isolation, but is understandable from context. This is particularly common in familiar compounds, such as in the following examples:
in
in
in
In some cases, a component has been simplified when part of other characters, but has not been simplified in isolation, or has been simplified in some characters but not others. In that case, simplifying it in isolation can be used as common ryakuji. For example, is used in isolation, but in compounds has been simplified to, such as to. Using in isolation, such as when writing shin-sotsu "newly graduated" as, is unofficial ryakuji. As another example, has been simplified to in some characters, such as to, but only to in isolation or other characters. Thus simplifying the in to is found in ryakuji. More unusual examples come from calligraphic abbreviations, or more formally from printed forms of calligraphic forms: a standard character is first written in a calligraphic form, then this is converted back to print script in a simplified form. This is the same principle as graphical simplifications such as, and of various simplifications above, such as. A conspicuous informal example is , which is rather frequently seen on store signs. Other examples include ; and replacing the center of with two, as in the bottom of. has various such simplifications. In Niigata, the second character is rare and complex, and is thus simplified as.
Derived characters
Derived characters accordingly also have derived ryakuji, as in these characters derived from : Similarly, the simplification is often used in fish compounds, such as sushi, particularly in signs.
Phonetic simplifications
Some ryakuji are simplified phono-semantic characters, retaining a radical as semantic and replacing the rest of the character with a katakana phonetic for the on reading, e.g., may be simplified as + : Another example is sō, replacing the by so. This may also be done using Latin characters; for example, the character may be simplified to "": the radical placed over the letter K; this is particularly common in law school. Similarly, as in Keio University may be simplified to "": the letters K and O respectively placed inside the radical. In this case the pronunciation of "KO" sounds like the actual name "Keiō", hence the use. The character has a number of ryakuji, as it is a commonly used character with many strokes ; in addition to the above phono-semantic simplification, it also has a number of purely graphical simplifications:
