Dakuten

, colloquially ten-ten ("dot dot"), is a diacritic sign most often used in the Japanese kana syllabaries to indicate that the consonant of a syllable should be pronounced voiced. Handakuten (半濁点), colloquially maru ("circle"), is a diacritic used with the kana for syllables starting with h to indicate that they should instead be pronounced with [p]. The kun-yomi pronunciation of the character 濁 is nigori; hence the daku-ten may also be called the nigori-ten. The meaning of this character—muddy or turbid—is a hint that the theory behind this kind of spelling device originally came from China, where consonant sounds were traditionally described by terms such as clear, half-clear, muddy, and so on. In informal writing it is occasionally used on vowels to indicate a shocked or strangled articulation.

The dakuten became standard practice in the Tokugawa era; previously, written Japanese did not distinguish between voiceless and voiced consonants.

Glyphs

The dakuten resembles a quotation mark, while the handakuten is a small circle, similar to a degree sign, both placed at the top right corner of a kana character:

□゛ dakuten (U+3099)

□゜ handakuten (U+309A)

The dakuten glyph is drawn identically in both the hiragana and katakana scripts and so is the handakuten. The combining characters are rarely used in full-width Japanese characters, as Unicode and all common multibyte Japanese encodings provide precomposed glyphs for all possible dakuten and handakuten character combinations in the standard hiragana and katakana ranges. However, combining characters are required in half-width katakana, which does not provide any precomposed characters in order to fit within a single byte.

Quotes in written Japanese often use corner brackets (「」), so the similarity of dakuten and quotation marks (") is not a problem.

Phonetic shifts

See also: hiragana, Japanese phonology

The following table summarizes the phonetic shifts caused by the dakuten and handakuten. Literally, syllables with dakuten are "muddy sounds" (濁音 dakuon), while those without are "clear sounds" (清音 seion), but the handakuten (lit. "half-muddy mark") does not follow this pattern.

none	dakuten	handakuten
か ka	が ga	(か゚ nga)
さ sa	ざ za
た ta	だ da
は ha	ば ba	ぱ pa

Handakuten on ka, ki, ku, ke, ko are not used in normal Japanese writing, but may be used by linguists and in dictionaries to represent the sound of ng in singing (ŋ), which is an allophone of /g/ in many dialects of Japanese. This is called bidakuon (鼻濁音), "nasal muddy sound".

In katakana only, the dakuten may also be added to the character ウ u and a small vowel character to create a /v/ sound, as in ヴァ va. As "V" does not exist in Japanese, this usage applies only to some modern loanwords and remains relatively uncommon, and e.g. Venus is typically transliterated as ビーナス biinasu instead of ヴィーナス viinasu. Many Japanese, however, would pronounce both the same, with a /b/ sound, and may or may not recognize them as representing the same word.

An even less common method is to add dakuten to the w- series, reviving the now defunct characters for /wi/ (ヰ) and /we/ (ヱ). /vu/ is represented by using /u/, as above; /wo/ becomes /vo/ despite its W normally being silent. Precomposed characters exist for this method as well (/va/ ヷ /vi/ ヸ /vu/ ヴ /ve/ ヹ /vo/ ヺ), although most IMEs do not have a convenient way to enter them.

Kana iteration marks

See also: Iteration mark

The dakuten can also be added to hiragana and katakana iteration marks, indicating that the previous kana is repeated with voicing:

	none	dakuten
hiragana	ゝ	ゞ
katakana	ヽ	ヾ

Both signs are relatively rare, but can occasionally be found in personal names such as Misuzu (みすゞ). In these cases the pronunciation is identical to writing the kana out in full. There is also a longer multi-character repeat mark called kunojiten, which is only used in vertical writing, and this also can have a dakuten added.