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𝕆

Mathematical Double-struck Capital O Symbol

𝕆 is the Mathematical Double-Struck Capital O character (U+1D546).

U+1D546

𝕆 (U+1D546) is a double-struck, capital letter O used in specialized text. It’s common in mathematical notation where a distinctive “O” glyph is needed. Use it for copy/paste in documents, web pages, and design mockups.

Mathematical Double-struck Capital O Symbol Meaning

𝕆 is Unicode’s “MATHEMATICAL DOUBLE-STRUCK CAPITAL O” (U+1D546). The double-stroke styling distinguishes it from the regular Latin capital O and from other mathematical O variants. In practice, it’s most often used in mathematical contexts where authors want a specific symbol appearance—such as labeling sets or operators in notation conventions, or writing text that must match a particular font style. Because it belongs to the Mathematical alphanumeric symbols block, appearance depends on the font you’re using. If your font doesn’t support it, you may see a fallback or missing glyph.

Common uses

  • Typing mathematical notation that requires the double-struck “O” glyph
  • Labeling variables or symbols in math-heavy documents and worksheets
  • Designing posters or slides that include specialized mathematical typography
  • Creating consistent symbol styling in academic writing templates
  • Using the character in UI/mockups where a specific mathematical letterform is required

Examples

𝕆 Mathematical Double-Struck Capital O

  • 𝕆Let 𝕆 be a set of outcomes.
  • 𝕆Define 𝕆 as the set of integers with a chosen property.
  • 𝕆We consider 𝕆 under the given operation.
  • 𝕆The symbol 𝕆 appears in the second equation.
  • 𝕆Font check: verify 𝕆 renders correctly in your document.

Variations

Ready to copy

Technical codes

UnicodeU+1D546
HTML Entity𝕆
HTML Code𝕆
CSS\1D546

FAQ

What does the Mathematical Double-struck Capital O symbol mean?

𝕆 is Unicode’s “MATHEMATICAL DOUBLE-STRUCK CAPITAL O” (U+1D546). The double-stroke styling distinguishes it from the regular Latin capital O and from other mathematical O variants. In practice, it’s most often used in mathematical contexts where authors want a specific symbol appearance—such as labeling sets or operators in notation conventions, or writing text that must match a particular font style. Because it belongs to the Mathematical alphanumeric symbols block, appearance depends on the font you’re using. If your font doesn’t support it, you may see a fallback or missing glyph.

How do I type or copy 𝕆?

Copy it directly from this page, or use its Unicode code point U+1D546 (HTML: 𝕆, CSS escape: \\1D546, JavaScript: \\u{1D546}).

Why does 𝕆 look different from a normal capital O?

𝕆 is a double-struck mathematical glyph. Its stylized stroke gives it a distinct appearance compared to the regular Latin capital O.

Will 𝕆 display correctly on all devices?

It depends on font support for the Mathematical alphanumeric symbols block. If a font lacks the glyph, you may see a fallback character.

Can I use 𝕆 in HTML or CSS?

Yes. For example, use HTML entity 𝕆 or CSS escape \\1D546 to include the character reliably when supported.