⊊

Math Operator 135

Unicode
U+228A
Category
Math
HTML Entity
⊊
CSS
\228A
The ⊊ symbol, officially known as "Subset Of With Not Equal To," is a mathematical operator used in set theory to represent a proper (or strict) subset. It specifically indicates that one set is completely contained within another, but the two sets are not identical. While rarely used in casual texting, mathematicians and computer scientists rely on it to eliminate the ambiguity of the standard subset symbol (⊂) in formal proofs and academic papers.

How to Type

Windows
Win + . (period) to open the emoji panel and search "subset", or type 228A followed by Alt + X in Microsoft Word
macOS
Control + Command + Space to open the Character Viewer and search "subset"
HTML
⊊ or ⊊

In Programming

In LaTeX and Markdown math blocks, this symbol is rendered using the `\subsetneq` command. While it isn't part of standard programming languages, it frequently appears in academic documentation, type theory, and formal logic provers like Lean or Coq.

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Tags

A ⊊ B meaning HTML ⊊ LaTeX proper subset U+228A \subsetneq \varsubsetneq inclusion mathematics proper subset proper subset symbol set theory strict subset strict subset not equal subset not equal to type proper subset symbol

Related Symbols

± Plus Minus Sign × Multiplication Sign ÷ Division Sign ≠ Not Equal To ≈ Approximately Equal To ∞ Infinity √ Square Root ∑ Summation ∫ Integral π Pi ≤ Less Than or Equal To ≥ Greater Than or Equal To