∇
∇ Nabla / Del Symbol
Nabla (∇), also called del, is the vector differential operator — it builds the gradient, divergence and curl. It is the mathematical “upside-down triangle”.
Also known as: upside down triangle, upside down triangle symbol, inverted triangle symbol, nabla, del operator, gradient symbol.
Codes
| Symbol | ∇ | |
| Unicode | U+2207 | |
| HTML entity (named) | ∇ | |
| HTML entity (decimal) | ∇ | |
| HTML entity (hex) | ∇ | |
| CSS | \2207 | |
| LaTeX | \nabla |
How to type ∇ (Nabla / Del Symbol)
Windows2207, Alt + X
In Word, type 2207 then press Alt + X. Elsewhere, copy ∇ above or use Character Map (search “nabla”).
Mac
Open Character Viewer (Control + Cmd + Space) and search “nabla”, or copy ∇ above.
Microsoft Word2207, Alt + X
Type 2207, then press Alt + X to convert it to ∇.
Google Docs
Insert → Special characters, then search “nabla”. In an equation, \nabla followed by a space also works.
LaTeX\nabla
Use \nabla in math mode: \nabla f for the gradient, \nabla \cdot F for divergence, \nabla \times F for curl.
Usage
- ∇f is the gradient of f — the vector of its partial derivatives, pointing in the direction of steepest increase.
- ∇ · F is the divergence of a vector field and ∇ × F is its curl. In machine learning, ∇ is what gradient descent descends.
- Which upside-down triangle do you want? ∇ (U+2207) is the math operator. ▽ (U+25BD) is the geometric white down-pointing triangle, and ▼ (U+25BC) its filled version — those are shapes, not operators. They look alike; only ∇ carries mathematical meaning.
- Nabla is not a Greek letter, despite the look. The name comes from a Hellenistic harp of that shape.