The union sign ∪ combines two sets into everything found in either, so A ∪ B holds all their members with no duplicates. Type 222A then Alt+X in Word. The opening faces up like a cup, which is the memory aid for telling it from intersection.
01 All shortcuts at a glance
| Platform | Shortcut | |
|---|---|---|
| Windows (any app) | Win+. or Win+; emoji/symbol picker, or Character Map (Win+R → charmap) |
|
| Mac | Control+Command+Space to open Character Viewer, search "Union" |
|
| Word / Outlook | Type 222A, then press Alt+X |
|
| Linux (IBus) | Ctrl+Shift+U, then 222a, then Enter |
|
| HTML / CSS | ∪ · \222a (CSS) |
02 Step by step, per platform
A real, followable procedure for every platform, not a thin restatement of the shortcut.
Windows
- Open Character Map: Win+R, type charmap, press Enter.
- Search or scroll for Union (U+222A).
- Select it, click Copy, then paste where you need it.
Mac
- Press Control+Command+Space to open the Character Viewer.
- Type "Union" in the search field.
- Double-click the result to insert it.
Microsoft Word
- Type 222A.
- Press Alt+X immediately after, it converts the hex code to ∪.
03 Characters in this set
04 Troubleshooting & confusables
| Looks like it | But it's actually | When to use |
|---|---|---|
| ∩ (U+2229) | Intersection, opening downward | The opposite operation, keeping only what both sets share. |
| U as a letter | The Latin capital U | A handwritten substitute. The symbol is symmetrical and has no serifs. |
| ⋃ (U+22C3) | N-ary union | The large operator for taking the union of an indexed family of sets. |
05 FAQ
What is the Unicode code point for union?
It is U+222A, decimal 8746. There is no Windows Alt code for it.
Does a union keep duplicates?
No. A set contains each element once, so an item in both sets still appears once in the union. Multisets behave differently, but plain set union does not.
How do I remember the direction?
Union opens upward like a cup that catches everything from both sets. Intersection is the cap over only what they share.
Is it the same as logical or?
It mirrors it. An element is in A ∪ B exactly when it is in A or in B, using the inclusive or. That correspondence is why ∨ and ∪ look alike.
What is the large union symbol?
U+22C3, the n-ary union, used with an index below it to combine a whole family of sets in one expression.