U+01D1 "Ǒ" Latin Capital Letter O with Caron Unicode Character
U+01D1 "Ǒ" Latin Capital Letter O with Caron is a precomposed character in the Latin script that represents the letter O combined with a caron, or háček, which is a diacritical mark resembling an inverted breve. This character is used primarily in the transcription of certain tonal or phonetic systems, such as the International Phonetic Alphabet or romanization schemes for languages like Hmong or Mandarin Chinese, where the caron indicates a falling then rising tone. It appears less commonly than its lowercase counterpart, but facilitates unambiguous representation of this specific tonal contour in digital text. The character is encoded in the Unicode standard as a single codepoint for compatibility and ease of use with legacy character sets that supported precomposed forms.
General Properties
| Code Point | U+01D1 |
| Version Added | 1.1 |
| Name | Latin Capital Letter O with Caron |
| Unicode 1.0 Name | Latin Capital Letter O Hacek |
| Block | Latin Extended-B |
| General Category | Uppercase Letter |
| Canonical Combining Class | Not Reordered |
| Bidirectional Class | Left To Right |
| Decomposition Type | Canonical |
| Decomposition Mapping | "O" U+004F Latin Capital Letter O "̌" U+030C Combining Caron |
Encodings
| HTML Decimal Encoding | Ǒ |
| HTML Hex Encoding | Ǒ |
| UTF-8 Encoding | 0xC7 0x91 |
| UTF-16 Encoding | 0x01D1 |
| UTF-32 Encoding | 0x000001D1 |
| C/C++/Java Escape | \u01d1 |
Unicode Properties
| NFC Quick Check | Yes |
| NFKC Quick Check | Yes |
| Numeric Type | None |
| Numeric Value | NaN |
| Line Break | Alphabetic |
| Uppercase | Yes |
| Simple Lowercase Code Point | "ǒ" U+01D2 Latin Small Letter O with Caron |
| Lowercase Code Point | "ǒ" U+01D2 Latin Small Letter O with Caron |
| Simple Case Folding | "ǒ" U+01D2 Latin Small Letter O with Caron |
| Case Folding | "ǒ" U+01D2 Latin Small Letter O with Caron |
| Cased | Yes |
| Changes When Casefolded | Yes |
| Changes When Casemapped | Yes |
| Changes When Lowercased | Yes |
| Changes When NFKC Casefolded | Yes |
| NFKC Casefold | "ǒ" U+01D2 Latin Small Letter O with Caron |
| NFKC Simple Casefold | "ǒ" U+01D2 Latin Small Letter O with Caron |
| Script | Latin |
| Script Extensions | Latin |
| Indic Syllabic Category | Other |
| ID Start | Yes |
| XID Start | Yes |
| ID Continue | Yes |
| XID Continue | Yes |
| Alphabetic | Yes |
| Vertical Orientation | Rotated |
| Grapheme Base | Yes |
| Grapheme Cluster Break | Other |
| Word Break | Alphabetic letter |
| Sentence Break | Upper |