Mathematical Bold Italic Small Delta Symbol
𝜹 is a Unicode mathematical symbol: the bold italic small delta used in math and technical typesetting.
U+1D739
𝜹 is a specialized Unicode math character. It belongs to the “MATHEMATICAL BOLD ITALIC SMALL DELTA” set and is typically used when authors need a delta-looking glyph with bold-italic styling.
Mathematical Bold Italic Small Delta Symbol Meaning
𝜹 is the Unicode character named “MATHEMATICAL BOLD ITALIC SMALL DELTA” (code point U+1D739). It is a typographic variant of the Greek letter delta designed for mathematical contexts. Because it is bold and italic, it’s useful when you want the delta symbol to match a particular math style—such as vectors, parameters, or variables presented in bold italic form. In everyday text it usually appears only inside formulas, technical writing, or styled mathematical notation. If you need a normal (non-bold, non-italic) delta, you should use a different Unicode character rather than this styled variant.
Common uses
- •Math typesetting where a bold-italic delta variable is required
- •Designing consistent notation in scientific or engineering documents
- •Labeling parameters or constants in custom equation layouts
- •Creating styled math text for diagrams and UI math rendering
- •Using in markup systems that support Unicode math symbols
Examples
𝜹 — Mathematical Bold Italic Small Delta
- 𝜹Let 𝜹 denote a small change in quantity X.
- 𝜹We write 𝜹 = 𝜹0 + 𝜹1 in the model.
- 𝜹Compute the update using the bold-italic delta 𝜹.
- 𝜹The matrix uses 𝜹 as a parameter in each block.
- 𝜹In the derivation, 𝜹 is treated as constant.
Variations
Ready to copy
Technical codes
| Unicode | U+1D739 | |
| HTML Entity | 𝜹 | |
| HTML Code | 𝜹 | |
| CSS | \1D739 | |
| Decimal | 120633 |
How to type Mathematical Bold Italic Small Delta Symbol (𝜹)
On Windows
In Word, type 1D739 then press Alt + X. Or open the emoji picker with Windows key + period.
On Mac
Press Control + Command + Space to open Character Viewer and search for the character.
On Linux
Press Control + Shift + U, type 1d739, then press Enter or Space.
Anywhere
Copy 𝜹 with the button above and paste it wherever you need it — this works on every device and in every app, with no keyboard shortcut to remember.
FAQ
What does the Mathematical Bold Italic Small Delta symbol mean?
𝜹 is the Unicode character named “MATHEMATICAL BOLD ITALIC SMALL DELTA” (code point U+1D739). It is a typographic variant of the Greek letter delta designed for mathematical contexts. Because it is bold and italic, it’s useful when you want the delta symbol to match a particular math style—such as vectors, parameters, or variables presented in bold italic form. In everyday text it usually appears only inside formulas, technical writing, or styled mathematical notation. If you need a normal (non-bold, non-italic) delta, you should use a different Unicode character rather than this styled variant.
What Unicode character is 𝜹?
𝜹 is U+1D739, named “MATHEMATICAL BOLD ITALIC SMALL DELTA.”
How do I copy 𝜹?
Copy the character directly from this page. You can also insert it via its Unicode code point (U+1D739) in editors that support Unicode input.
Is 𝜹 the same as the regular Greek delta (δ)?
No. 𝜹 is a bold italic variant intended for mathematical typesetting, while δ is the standard Greek small delta.
Will 𝜹 display correctly in all fonts?
Not always. 𝜹 is a Unicode math symbol, and display depends on whether your font and application include the U+1D739 glyph.