HTML Entity for N-Ary Union (⋃)

Beginner

5 min read

Updated: Sep 2026

1 example

Unicode U+22C3

HTML Entity for N-Ary Union (U+22C3) tutorial illustration

Definition

What Is the N-Ary Union Entity?

N-Ary Union (⋃) is the math operator at Unicode U+22C3 for the union of an indexed family of sets. HTML5 provides &bigcup;. Example: ⋃_i A_i.

Remember

Character     ⋃
Unicode       U+22C3
Named entity  &bigcup;
Hex entity    &#x22C3;
Decimal       &#8899;
CSS escape    \22C3

Named, hex, decimal, CSS, and a typed character all produce the same glyph: ⋃.

Reference

Quick Reference

One table for every form you will actually use.

Form	Code	Where it goes
Named entity	`&bigcup;`	HTML markup (preferred)
Direct character	`⋃`	UTF-8 HTML text
Hex entity	`⋃`	HTML markup
Decimal entity	`⋃`	HTML markup
CSS escape	`\22C3`	Stylesheet `content`

When to Use Which

Situation	Use
Indexed union of many sets	`&bigcup;`
Need an entity in HTML source	`&bigcup;`, `⋃`, or `⋃`
Generated text via `::before` / `::after`	`content: "\22C3"`
Binary union of two sets (∪)	`∪` — not `&bigcup;`
N-ary intersection (⋂)	See N-Ary Intersection — `&bigcap;`

See it

Live Preview

Union alone, indexed, and beside related operators.

Example ⋃_i∈I A_i

Large glyph ⋃

Named entity &bigcup; → ⋃

vs ∪ / ⋂ / ∑ ⋃ | ∪ | ⋂ | ∑

With entities Named: ⋃ | Hex: ⋃ | Decimal: ⋃

Code

Complete HTML Example

One page that shows the N-Ary Union with named, hex, decimal, and CSS forms. Use View Output or open the live editor.

Named + Hex + Decimal + CSS

Four ways to produce ⋃ in a single document.

html

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>N-Ary Union (⋃)</title>
  <style>
    #point::after {
      content: "\22C3";
    }
  </style>
</head>
<body>
  <p>Using Named Entity: &bigcup;</p>
  <p>Using Hex Code: &#x22C3;</p>
  <p>Using HTML Code: &#8899;</p>
  <p id="point">Using CSS Entity: </p>
  <p>Formula: &bigcup;<sub>i</sub> A<sub>i</sub></p>
</body>
</html>

Try It Yourself

How It Works

1. Named: &bigcup; is the clearest HTML form and renders ⋃.

2. Hex: U+22C3 → ⋃ in HTML. Same result as the named entity.

3. Decimal: same code point as 8899 → ⋃. Same result as hex and named.

4. CSS: use \22C3 in content (not an HTML entity). #point::after appends that ⋃ after the paragraph text.

Pitfalls & Tips

Common mistakes when working with the N-Ary Union.

Prefer

Use `&bigcup;`

The named form is clearer than numeric references and is defined in HTML5.

vs ∪

Not binary union

∪ is ∪ (U+222A) for two sets. Use &bigcup; for indexed families.

vs ⋂

Not intersection

&bigcap; is ⋂ (n-ary intersection). Union and intersection are different operations.

CSS vs HTML

Do not mix escapes

\22C3 belongs in CSS. &bigcup; / ⋃ / ⋃ belong in HTML.

Encoding

Declare UTF-8

If you type ⋃ directly, keep <meta charset="UTF-8"> so the file is not misread.

Semicolon

End references

Always finish with ; — write &bigcup;, not &bigcup.

Compatibility

Browser Support

N-Ary Union (U+22C3) and its entity forms (&bigcup;, ⋃, ⋃, CSS \\22C3) are supported in all mainstream browsers with a Unicode-capable font.

✓ Universal support

N-Ary Union (&bigcup;)

Encode with named, hex, decimal, or CSS escape — or type ⋃ directly in UTF-8 HTML.

100% Browser coverage

Google Chrome Supported

Yes

Microsoft Edge Supported

Yes

Mozilla Firefox Supported

Yes

Apple Safari Supported

Yes

Opera Supported

Yes

Internet Explorer IE 9+

Yes*

U+22C3 / &bigcup; Full support

Bottom line: Prefer &bigcup; in math HTML. Use \\22C3 only inside CSS content.

Remember

Key Takeaways

Unicode: N-Ary Union is U+22C3 (decimal 8899).
HTML: prefer &bigcup;.
CSS: use \22C3 inside content for generated text.
Lookalike: not ∪ (∪) — use &bigcup; for indexed families.

One line: U+22C3 → prefer &bigcup; (also ⋃ / CSS \22C3).

Frequently Asked Questions

How do I display the N-Ary Union in HTML using entities?

Use &bigcup; (named), ⋃ (hex), ⋃ (decimal), or the CSS escape \22C3 in the content property. All render ⋃. Prefer &bigcup; in math HTML.

What is the Unicode value for the N-Ary Union?

U+22C3 (N-ARY UNION). Hex 22C3, decimal 8899. It belongs to the Mathematical Operators block.

Is there a named HTML entity for U+22C3?

Yes. HTML5 defines &bigcup; for ⋃.

When should I use this HTML entity?

Use it in set theory and formal math when writing an n-ary (indexed) union — for example ⋃ᵢ Aᵢ.

What is the difference between HTML code and CSS entity for U+22C3?

HTML entities (&bigcup;, ⋃, or ⋃) go in markup. The CSS escape \22C3 is used in stylesheets (usually in the content property of ::before/::after). Both render ⋃.

Is ⋃ the same as ∪ or ⋂?

No. N-ary union is &bigcup; (⋃, U+22C3). Binary union is ∪ (∪, U+222A). N-ary intersection is &bigcap; (⋂, U+22C2). Different operators.

Did you know?

N-Ary Union is Unicode U+22C3 (decimal 8899) — in Mathematical Operators. HTML5 provides &bigcup;. It denotes the union of an indexed family of sets. Related: Intersection &bigcap; (⋂), binary union ∪ (∪), Summation ∑ (∑).

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About the author

Mari Selvan M P 🔗

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