Open Subset Symbol
⟃ denotes an open subset in mathematics, often used in topology and related fields.
U+27C3
The symbol ⟃ is commonly read as “open subset.” It appears in mathematical writing where sets are classified by openness. You can copy it directly or insert it using its Unicode code point.
Open Subset Symbol Meaning
⟃ (Unicode U+27C3) is the “OPEN SUBSET” symbol. In mathematics, it’s typically used to indicate that a set is an open subset of a topological space. This notation helps express properties that depend on the topology, such as statements involving open sets, neighborhoods, and continuity. Depending on the context, you may see it paired with a specific set name, for example “⟃A” meaning “A is open.” When writing or typesetting, using the correct Unicode character ensures consistent appearance across modern fonts and tools.
Common uses
- •Labeling a set as open in topology notes or proofs
- •Annotating diagrams or definitions with “open subset” markers
- •Writing educational content about topological spaces
- •Indicating openness of a subset in formal problem statements
- •Adding clear set-property notation in technical documents
Examples
⟃ Open Subset Symbol
- ⟃Let ⟃U be an open subset of X.
- ⟃Assume A is ⟃ in X.
- ⟃Since ⟃G ⊆ X, G is open.
- ⟃The collection of ⟃ sets forms a topology.
- ⟃We take ⟃O around a point.
Variations
Ready to copy
Technical codes
| Unicode | U+27C3 | |
| HTML Entity | ⟃ | |
| HTML Code | ⟃ | |
| CSS | \27C3 | |
| Alt Code | Alt + 10179 | |
| Decimal | 10179 |
How to type Open Subset Symbol (⟃)
On Windows
Hold Alt and type 10179 on the numeric keypad. In Word, type 27C3 then press Alt + X.
On Mac
Switch to the Unicode Hex Input keyboard, then hold Option and type 27C3. Or press Control + Command + Space and search.
On Linux
Press Control + Shift + U, type 27c3, 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 symbol ⟃ mean?
⟃ is the “OPEN SUBSET” symbol, used to indicate that a set is open in a topological space.
What is the Unicode code point for ⟃?
The Unicode code point for ⟃ is U+27C3.
How can I type ⟃ on websites using HTML?
Use the HTML entity: ⟃.
How do I insert ⟃ using CSS or JavaScript escapes?
CSS escape: \\27C3. JavaScript escape: \\u{27C3}.