Closed Subset Symbol
⫏ denotes a closed subset in mathematical writing and typesetting.
U+2ACF
The symbol ⫏ is known as the closed subset symbol. It’s commonly used when describing sets with topological or analysis properties. You can copy it directly or use its Unicode/HTML codes in documents and web pages.
Closed Subset Symbol Meaning
⫏ (Unicode name: CLOSED SUBSET, U+2ACF) is a math symbol used to indicate that a set is closed. In topology and related areas of mathematics, “closed subset” refers to a subset whose complement is open, or equivalently one that contains all its limit points (depending on the context). In practice, you’ll see ⫏ in typed formulas, set statements, or proof annotations to distinguish closed sets from open ones. It’s primarily a notation symbol rather than a general-purpose punctuation mark, so it fits best in math expressions, lecture notes, and academic documents.
Common uses
- •Labeling a set as closed in topology or analysis statements
- •Annotating steps in proofs where closedness is required
- •Formatting mathematical definitions involving closed subsets
- •Writing concise shorthand in homework solutions or lecture notes
- •Adding clear set-property notation in scientific papers and reports
Examples
⫏ Closed Subset Symbol
- ⫏Let A ⫏ X be a closed subset of the space X.
- ⫏Assume B ⫏ ℝ is closed in the usual topology.
- ⫏Since A is ⫏, it contains its limit points.
- ⫏We show that the preimage of C under f is ⫏.
- ⫏Define D as a ⫏ subset with the stated properties.
Variations
Ready to copy
Technical codes
| Unicode | U+2ACF | |
| HTML Entity | ⫏ | |
| HTML Code | ⫏ | |
| CSS | \2ACF | |
| Alt Code | Alt + 10959 | |
| Decimal | 10959 |
How to type Closed Subset Symbol (⫏)
On Windows
Hold Alt and type 10959 on the numeric keypad. In Word, type 2ACF then press Alt + X.
On Mac
Switch to the Unicode Hex Input keyboard, then hold Option and type 2ACF. Or press Control + Command + Space and search.
On Linux
Press Control + Shift + U, type 2acf, then press Enter or Space.
Anywhere
Copy ⫏ 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 Closed Subset symbol mean?
⫏ (Unicode name: CLOSED SUBSET, U+2ACF) is a math symbol used to indicate that a set is closed. In topology and related areas of mathematics, “closed subset” refers to a subset whose complement is open, or equivalently one that contains all its limit points (depending on the context). In practice, you’ll see ⫏ in typed formulas, set statements, or proof annotations to distinguish closed sets from open ones. It’s primarily a notation symbol rather than a general-purpose punctuation mark, so it fits best in math expressions, lecture notes, and academic documents.
What is the Unicode name and code point for ⫏?
The Unicode name is “CLOSED SUBSET” and the code point is U+2ACF.
How do I copy ⫏ into a web page?
You can paste the character directly, or use the HTML entity ⫏ in your markup.
Is ⫏ used for any meaning besides “closed subset”?
In common usage, ⫏ is specifically tied to the math notation for “closed subset,” especially in topology and analysis.
How can developers insert ⫏ using different escape formats?
Use CSS escape \\2ACF or JavaScript escape \\u{2ACF} (as provided for this symbol).