Handakuten

ﾞ

ﾟ

Dakuten

Diacritics in Latin & Greek
accent
acute( ´ )
double acute( ˝ )
grave( ` )
double grave( ̏ )
breve( ˘ )
inverted breve( ̑ )
caron, háček( ˇ )
cedilla( ¸ )
circumflex( ˆ )
diaeresis, umlaut( ¨ )
dot( · )
hook, hook above( ̡ ̢ ̉ )
horn( ̛ )
iota subscript( ͅ )
macron( ¯ )
ogonek, nosinė( ˛ )
perispomene( ͂ )
ring( ˚, ˳ )
rough breathing( ῾ )
smooth breathing( ᾿ )
Marks sometimes used as diacritics
apostrophe( ’ )
bar( ◌̸ )
colon( : )
comma( , )
hyphen( ˗ )
tilde( ~ )
Diacritical marks in other scripts
Arabic diacritics
Early Cyrillic diacritics
kamora( ҄ )
pokrytie( ҇ )
titlo( ҃ )
Gurmukhī diacritics
Hebrew diacritics
Indic diacritics
anusvara( ं ং ം )
chandrabindu( ँ ఁ )
nukta( ़ )
virama( ् ് ్ ් ್ )
chandrakkala( ് )
IPA diacritics
Japanese diacritics
dakuten( ﾞ )
handakuten( ﾟ )
Khmer diacritics
Syriac diacritics
Thai diacritics
Related
Dotted circle◌
Punctuation marks
Logic symbols

Dakuten (濁点^?, lit. "voicing mark"), colloquially ten-ten (点々^?, "dots"), is a diacritic sign most often used in the Japanese kana syllabaries to indicate that the consonant of a syllable should be pronounced voiced, for instance, on sounds that have undergone rendaku (sequential voicing).

Handakuten (半濁点^?), colloquially maru (丸^?, "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. This character, meaning muddy or turbid, stems from historical Chinese phonology, where consonants were traditionally classified as clear (清 "voiceless"), lesser-clear (次清 "aspirated") and muddy (濁 "voiced"). (See: Middle Chinese#Initials)

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Wikipedia