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O (kana)

Character of the Japanese writing system

O (hiragana: , katakana: ) is one of the Japanese kana, each of which represents one mora. In the modern Japanese system of alphabetical order, they occupy the fifth place in the modern Gojūon (五十音) system of collating kana. In the Iroha, they occupy the 27th, between and . In the table at right (ordered by columns, from right to left), お lies in the first column (あ行, "column A") and the fifth row (お段, "row O"). Both represent [o].

Form Rōmaji Hiragana Katakana
Normal a/i/u/e/o
(あ行 a-gyō)
o
ou
oo
ō
おう, おぅ
おお, おぉ
おー
オウ, オゥ
オオ, オォ
オー

01Derivation

お and オ originate, via man'yōgana, from the kanji 於.

Stroke order in writing お
Stroke order in writing お

02Variant forms

Scaled-down versions of the kana (ぉ, ォ) are used to express morae foreign to the Japanese language, such as フォ (fo).

Stroke order in writing オ
Stroke order in writing オ

03Stroke order

The hiragana お is made with three strokes:

  1. A horizontal line from left to right.
  2. A stroke consisting of a vertical line, a small diagonal line going upwards and to the left, and an open curve heading right and downwards.
  3. A small curved stroke on the right.

The katakana オ is made with three strokes:

  1. At the top, a horizontal stroke from left to right.
  2. A downward vertical stroke cutting through the first stroke, with a small hook at the end facing left.
  3. At the intersection of the first two strokes, a diagonal line going downwards and to the left.
Stroke order in writing お
Stroke order in writing お

04Other communicative representations

  • Full Braille representation
お / オ in Japanese Braille
お / オ
o
おう / オー
ō/ou
+う / +ー
chōon*

* When lengthening "-o" morae in Japanese braille, a chōon is always used, as in standard katakana usage instead of adding an お / オ.

Character information
Preview
Unicode name HIRAGANA LETTER O KATAKANA LETTER O HALFWIDTH KATAKANA LETTER O CIRCLED KATAKANA O
Encodingsdecimalhexdechexdechexdechex
Unicode12362U+304A12458U+30AA65397U+FF7513012U+32D4
UTF-8227 129 138E3 81 8A227 130 170E3 82 AA239 189 181EF BD B5227 139 148E3 8B 94
Numeric character referenceおおオオオオ㋔㋔
Shift JIS130 16882 A8131 7383 49181B5
EUC-JP164 170A4 AA165 170A5 AA142 1818E B5
GB 18030164 170A4 AA165 170A5 AA132 49 151 5584 31 97 37129 57 210 4881 39 D2 30
EUC-KR / UHC170 170AA AA171 170AB AA
Big5 (non-ETEN kana)198 174C6 AE199 66C7 42
Big5 (ETEN / HKSCS)198 240C6 F0199 166C7 A6
Character information
Preview
Unicode name HIRAGANA LETTER SMALL O KATAKANA LETTER SMALL O HALFWIDTH KATAKANA LETTER SMALL O
Encodingsdecimalhexdechexdechex
Unicode12361U+304912457U+30A965387U+FF6B
UTF-8227 129 137E3 81 89227 130 169E3 82 A9239 189 171EF BD AB
Numeric character referenceぉぉォォォォ
Shift JIS130 16782 A7131 7283 48171AB
EUC-JP164 169A4 A9165 169A5 A9142 1718E AB
GB 18030164 169A4 A9165 169A5 A9132 49 150 5584 31 96 37
EUC-KR / UHC170 169AA A9171 169AB A9
Big5 (non-ETEN kana)198 173C6 AD199 65C7 41
Big5 (ETEN / HKSCS)198 239C6 EF199 165C7 A5
Stroke order in writing オ
Stroke order in writing オ
Watch videos about O (kana)Explainers and documentaries on YouTube (opens in a new tab)

Sources and credits

This article is adapted from the Wikipedia article O (kana), written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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