U+031B was added to Unicode in version 1.1 (1993). It belongs to the block Combining Diacritical Marks in the Basic Multilingual Plane.

This character is a Nonspacing Mark and inherits its script property from the preceding character.

The glyph is not a composition. It has a Ambiguous East Asian Width. In bidirectional context it acts as Nonspacing Mark and is not mirrored. In text U+031B behaves as Combining Mark regarding line breaks. It has type Extend for sentence and Extend for word breaks. The Grapheme Cluster Break is Extend.

The Wikipedia has the following information about this codepoint:

The horn (Vietnamese: dấu móc or dấu râu) is a diacritic mark attached to the top right corner of the letters o and u in the Vietnamese alphabet to give ơ and ư, unrounded variants of the vowel represented by the basic letter. In Vietnamese, it is rarely considered a separate diacritic; rather, the characters ơ and ư are considered separate from o and u.


System Representation
UTF-16 03 1B
UTF-32 00 00 03 1B
URL-Quoted %CC%9B
HTML-Escape ̛
Wrong windows-1252 Mojibake ̛

Related Characters

  • Ơ
  • ơ
  • Ư
  • ư


Complete Record

Property Value
Age (age) 1.1
Unicode Name (na) COMBINING HORN
Unicode 1 Name (na1) NON-SPACING HORN
Block (blk) Diacriticals
General Category (gc) Nonspacing Mark
Script (sc) Inherited
Bidirectional Category (bc) Nonspacing Mark
Combining Class (ccc) Attached Above Right
Decomposition Type (dt) None
Decomposition Mapping (dm) ̛
Lowercase (Lower)
Simple Lowercase Mapping (slc) ̛
Lowercase Mapping (lc) ̛
Uppercase (Upper)
Simple Uppercase Mapping (suc) ̛
Uppercase Mapping (uc) ̛
Simple Titlecase Mapping (stc) ̛
Titlecase Mapping (tc) ̛
Case Folding (cf) ̛
ASCII Hex Digit (AHex)
Alphabetic (Alpha)
Bidi Control (Bidi_C)
Bidi Mirrored (Bidi_M)
Bidi Paired Bracket (bpb) ̛
Bidi Paired Bracket Type (bpt) None
Cased (Cased)
Composition Exclusion (CE)
Case Ignorable (CI)
Full Composition Exclusion (Comp_Ex)
Changes When Casefolded (CWCF)
Changes When Casemapped (CWCM)
Changes When NFKC Casefolded (CWKCF)
Changes When Lowercased (CWL)
Changes When Titlecased (CWT)
Changes When Uppercased (CWU)
Dash (Dash)
Deprecated (Dep)
Default Ignorable Code Point (DI)
Diacritic (Dia)
East Asian Width (ea) Ambiguous
Extender (Ext)
FC NFKC Closure (FC_NFKC) ̛
Grapheme Cluster Break (GCB) Extend
Grapheme Base (Gr_Base)
Grapheme Extend (Gr_Ext)
Hex Digit (Hex)
Hangul Syllable Type (hst) Not Applicable
Hyphen (Hyphen)
ID Continue (IDC)
Ideographic (Ideo)
ID Start (IDS)
IDS Binary Operator (IDSB)
IDS Trinary Operator and (IDST)
Indic Positional Category (InPC) NA
Indic Syllabic Category (InSC) Other
ISO 10646 Comment (isc)
Joining Group (jg) No_Joining_Group
Join Control (Join_C)
Jamo Short Name (JSN)
Joining Type (jt) Transparent
Line Break (lb) Combining Mark
Logical Order Exception (LOE)
Math (Math)
Noncharacter Code Point (NChar)
NFC Quick Check (NFC_QC) Maybe
NFD Quick Check (NFD_QC) Yes
NFKC Casefold (NFKC_CF) ̛
NFKC Quick Check (NFKC_QC) Maybe
NFKD Quick Check (NFKD_QC) Yes
Numeric Type (nt) None
Numeric Value (nv) NaN
Other Alphabetic (OAlpha)
Other Default Ignorable Code Point (ODI)
Other Grapheme Extend (OGr_Ext)
Other ID Continue (OIDC)
Other ID Start (OIDS)
Other Lowercase (OLower)
Other Math (OMath)
Other Uppercase (OUpper)
Pattern Syntax (Pat_Syn)
Pattern White Space (Pat_WS)
Quotation Mark (QMark)
Radical (Radical)
Sentence Break (SB) Extend
Simple Case Folding (scf) ̛
Script Extension (scx) Inherited
Soft Dotted (SD)
STerm (STerm)
Terminal Punctuation (Term)
Unified Ideograph (UIdeo)
Variation Selector (VS)
Word Break (WB) Extend
White Space (WSpace)
XID Continue (XIDC)
XID Start (XIDS)
Expands On NFC (XO_NFC)
Expands On NFD (XO_NFD)
Expands On NFKC (XO_NFKC)
Expands On NFKD (XO_NFKD)