Square original of (⊐) is the Unicode character at U+2290 in Mathematical Operators. Official name: SQUARE ORIGINAL OF. It is a square-style “original of” / superset-like relation — the dual of square image of (⊏).
Remember
Character ⊐
Unicode U+2290
Named entity ⊐
Hex entity ⊐
Decimal ⊐
CSS escape \2290
Not the same ⊃ · ⊏ · ⊒
Prefer ⊐ in HTML markup (⊐ is an alias). You can also type ⊐ in UTF-8, or use numeric forms when needed. For ordinary superset, use ⊃ (⊃) instead.
Using Named Entity: ⊐
Using Hex Code: ⊐
Using HTML Code: ⊐
Using CSS Entity: ⊐
Typed directly: ⊐
Notation: A ⊐ B
How It Works
1. Named:⊐ is the HTML5 name for U+2290 → ⊐. Best default in markup.
2. Hex:U+2290 → ⊐ in HTML. Same glyph as the named form.
3. Decimal: same code point as 8848 → ⊐. Same result as hex and named.
4. CSS: use \2290 in content (not an HTML entity). #point::after appends that ⊐ after the paragraph text.
5. Typed / notation: paste ⊐ in UTF-8, or write A ⊐ B for a short relation.
Pitfalls & Tips
Common mistakes when working with ⊐.
vs ⊃
Not ordinary superset
U+2283 (⊃, ⊃) is the common superset symbol. U+2290 is the square-style original-of form.
vs ⊏
Not square image of
⊏ (U+228F, ⊏) is the dual relation. Do not swap it with ⊐.
Name
Remember ⊐
The named entity is ⊐ — not ⊃ (that is U+2283).
CSS vs HTML
Do not mix escapes
\2290 belongs in CSS strings. ⊐ / ⊐ / ⊐ belong in HTML.
Semicolon
End named entities
Always finish with ; — write ⊐, not &sqsup.
A11y
Name the relation in context
Screen readers may announce the symbol unevenly. Prefer nearby words like “square original of” when the glyph carries meaning alone.
Compatibility
Browser Support
Square original of (U+2290) and its entity forms (⊐, ⊐, ⊐, CSS \\2290) are supported in all mainstream browsers. Visible glyphs depend on Mathematical Operators font coverage.
✓ Universal support
Square Original Of (⊐)
Encode with named, hex, decimal, CSS escape, or type the character — same code point everywhere encoding is supported.
100%Browser coverage
Google ChromeSupported
Yes
Microsoft EdgeSupported
Yes
Mozilla FirefoxSupported
Yes
Apple SafariSupported
Yes
OperaSupported
Yes
Internet ExplorerAll versions
Yes
U+2290 / entitiesFull support
Bottom line: Prefer ⊐ in HTML. Use ⊐ / ⊐ when numeric form is required, and \\2290 only inside CSS content.
Remember
Key Takeaways
Unicode: square original of is U+2290 (decimal 8848) — glyph ⊐.
HTML: prefer ⊐ — also ⊐ / ⊐ / type ⊐.
CSS: use \2290 inside content for generated text.
Meaning:⊐ is square original of — not ⊃ (⊃), not ⊏.
Use ⊐ (named), ⊐ (hex), ⊐ (decimal), type ⊐ directly in UTF-8, or the CSS escape \2290 in content. Prefer ⊐ in normal HTML.
U+2290 (SQUARE ORIGINAL OF). Hex 2290, decimal 8848. It belongs to Mathematical Operators (U+2200–U+22FF).
Yes. Use ⊐ (or the alias ⊐). Numeric forms ⊐ and ⊐ also work.
No. ⊐ is U+2290 (⊐). ⊃ is U+2283 (⊃). ⊏ is U+228F (⊏, square image of).
Use it for square-original-of / square-superset-style notation in set theory and academic math — not as a substitute for ordinary superset ⊃.
HTML entities (⊐, ⊐, or ⊐) go in markup. The CSS escape \2290 goes in stylesheet strings (usually content on ::before/::after).
🤔
Did you know?
Square original of is Unicode U+2290 (decimal 8848) — glyph ⊐ in Mathematical Operators (U+2200–U+22FF). HTML5 names it ⊐ (also ⊐). Official name: SQUARE ORIGINAL OF. Do not confuse with superset U+2283 (⊃, ⊃) or square image of U+228F (⊏, ⊏).
