∉
Not An Element Of
- Unicode
- U+2209
- Category
- Math
- HTML Entity
- ∉
- CSS
- \2209
The ∉ (Not An Element Of) symbol is a fundamental mathematical notation used in set theory to indicate that a specific value or object does not belong to a given set. Created by adding a strikethrough to the standard "element of" symbol (∈), it is widely used in mathematical proofs, logic expressions, and academic textbooks. Outside of formal equations, it occasionally appears in technical documentation to visually represent exclusion or non-membership.
How to Type
- Windows
- Alt+8713
- macOS
- Control+Command+Space then search "Not An Element"
- Linux
- Ctrl+Shift+U 2209
- HTML
- ∉
In Programming
In LaTeX and math rendering engines, this symbol is generated using the \notin command. While rarely typed directly in source code, modern languages that support Unicode can use it within mathematical libraries or output strings to denote a value's absence from an array or collection.
Tags
crossed element symbol
excluded from set
exclusion
mathematics
negated element of
not belongs
not belongs to
not in set
not member
set exclusion notation
set theory
strikethrough element
∉ meaning