U+01A1 "ơ" Latin Small Letter O with Horn Unicode Character
Unicode Version 17.0
ơ
U+01A1 "ơ" Latin Small Letter O with Horn is a modified Latin letter used prominently in the Vietnamese alphabet, where it represents the sound of a mid-back rounded vowel with a distinctive horn-shaped diacritic attached to the upper right side of the letter "o". This character is essential for writing many Vietnamese words, distinguishing it from the plain "o" in the language's tonal system and appearing in common terms like "cơm" (rice) and "mới" (new). Its design originates from the adaptation of the Latin script to Vietnamese phonology, and it is encoded in the Latin Extended-B block of Unicode to support accurate digital text representation.
General Properties
| Code Point | U+01A1 |
| Version Added | 1.1 |
| Name | Latin Small Letter O with Horn |
| Unicode 1.0 Name | Latin Small Letter O Horn |
| Block | Latin Extended-B |
| General Category | Lowercase Letter |
| Canonical Combining Class | Not Reordered |
| Bidirectional Class | Left To Right |
| Decomposition Type | Canonical |
| Decomposition Mapping | "o" U+006F Latin Small Letter O "̛" U+031B Combining Horn |
Encodings
| HTML Decimal Encoding | ơ |
| HTML Hex Encoding | ơ |
| UTF-8 Encoding | 0xC6 0xA1 |
| UTF-16 Encoding | 0x01A1 |
| UTF-32 Encoding | 0x000001A1 |
| C/C++/Java Escape | \u01a1 |
Unicode Properties
| NFC Quick Check | Yes |
| NFKC Quick Check | Yes |
| Numeric Type | None |
| Numeric Value | NaN |
| Line Break | Alphabetic |
| Lowercase | Yes |
| Simple Uppercase Code Point | "Ơ" U+01A0 Latin Capital Letter O with Horn |
| Simple Titlecase Code Point | "Ơ" U+01A0 Latin Capital Letter O with Horn |
| Uppercase Code Point | "Ơ" U+01A0 Latin Capital Letter O with Horn |
| Titlecase Code Point | "Ơ" U+01A0 Latin Capital Letter O with Horn |
| Cased | Yes |
| Changes When Casemapped | Yes |
| Changes When Titlecased | Yes |
| Changes When Uppercased | Yes |
| 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 | Lower |