Transcription into Japanese

In contemporary Japanese writing, foreign-language loanwords and foreign names are normally written in the katakana script, which is one component of the Japanese writing system. As far as possible, sounds in the source language are matched to the nearest sounds in the Japanese language, and the result is transcribed using standard katakana characters, each of which represents one syllable (strictly mora). For example, America is written アメリカ (A-me-ri-ka). To accommodate various foreign-language sounds not present in Japanese, a system of extended katakana has also developed to augment standard katakana.

Katakana, like the other Japanese kana, hiragana, has a one-to-one correspondence between sounds and characters. Therefore, once the "Japanese sound" of a word is established, there is no ambiguity in its katakana spelling (unlike spelling in English, for example).

A much less common form of transcription, not covered in this article, uses kanji characters for their phonetic values. For information on this method see Ateji.

The most conspicuous result of transcription into Japanese is the insertion of vowels, often making words significantly longer. This is because Japanese phonology has (C)V(C) syllables (optional starting consonant, vowel, optional ending consonant): it does not allow consonant clusters at the start of a syllable, and the only ending consonant is either the nasal ン, n or a geminate consonant – indeed, these closed syllables are due to ancient Chinese loanwords, and originally Japanese was strictly (C)V.

Since Japanese has few closed syllables, syllable-final consonants in the source language are often represented using the -u (or sometimes -o or -i) kanas with implicitly silent vowels – though this vowel often is pronounced in Japanese – or the syllable coda is not represented at all. For example, the name Jim is written ジム (Ji-mu). A similar principle applies to consonant clusters; for example spring would be transcribed as スプリング (su-pu-ri-n-gu).

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