Complete Set Theory & Topology Symbols

This page contains 31 essential symbols used in set theory and topology. These symbols represent fundamental concepts across mathematics, including set relations, operations, cardinality, topological boundaries, and differential operators. Each symbol includes technical details for easy use in documents, web pages, and academic writing.

Element Relation Symbols

∈ is called the "Element Of Symbol". It indicates membership between an element and a set. Its Unicode is U+2208, the LaTeX command is \in, and the HTML entity is ∈.

∉ is called the "Not Element Of Symbol". It negates set membership. Its Unicode is U+2209, the LaTeX command is \notin, and the HTML entity is ∉.

∋ is called the "Contains Symbol". It is the reverse of the element-of symbol. Its Unicode is U+220B, the LaTeX command is \ni, and the HTML entity is ∋.

∌ is called the "Does Not Contain Symbol". It negates the contains relation. Its Unicode is U+220C, the LaTeX command is \not\ni, and the HTML entity is ∌.

Basic Subset & Superset Symbols

⊂ is called the "Subset Symbol". It indicates one set is contained in another. Its Unicode is U+2282, the LaTeX command is \subset, and the HTML entity is ⊂.

⊃ is called the "Superset Symbol". It indicates one set contains another. Its Unicode is U+2283, the LaTeX command is \supset, and the HTML entity is ⊃.

⊄ is called the "Not Subset Symbol". It negates the subset relation. Its Unicode is U+2284, the LaTeX command is \not\subset, and the HTML entity is ⊄.

⊅ is called the "Not Superset Symbol". It negates the superset relation. Its Unicode is U+2285, the LaTeX command is \not\supset, and the HTML entity is ⊅.

Subset Equality & Proper Subset Symbols

⊆ is called the "Subset Or Equal Symbol". It explicitly includes set equality. Its Unicode is U+2286, the LaTeX command is \subseteq, and the HTML entity is ⊆.

⊇ is called the "Superset Or Equal Symbol". It explicitly includes set equality. Its Unicode is U+2287, the LaTeX command is \supseteq, and the HTML entity is ⊇.

⊈ is called the "Not Subset Or Equal Symbol". It negates subset or equal. Its Unicode is U+2288, the LaTeX command is \nsubseteq, and the HTML entity is ⊈.

⊉ is called the "Not Superset Or Equal Symbol". It negates superset or equal. Its Unicode is U+2289, the LaTeX command is \nsupseteq, and the HTML entity is ⊉.

⊊ is called the "Proper Subset Symbol". It means strict inclusion without equality. Its Unicode is U+228A, the LaTeX command is \subsetneq, and the HTML entity is ⊊.

⊋ is called the "Proper Superset Symbol". It means strict containment without equality. Its Unicode is U+228B, the LaTeX command is \supsetneq, and the HTML entity is ⊋.

Intersection & Union Symbols

∩ is called the "Intersection Symbol". It represents the common elements of sets. Its Unicode is U+2229, the LaTeX command is \cap, and the HTML entity is ∩.

∪ is called the "Union Symbol". It represents all elements of combined sets. Its Unicode is U+222A, the LaTeX command is \cup, and the HTML entity is ∪.

⋂ is called the "N-ary Intersection Symbol". It is used for large intersections of set families. Its Unicode is U+22C2, the LaTeX command is \bigcap, and the HTML entity is ⋂.

⋃ is called the "N-ary Union Symbol". It is used for large unions of set families. Its Unicode is U+22C3, the LaTeX command is \bigcup, and the HTML entity is ⋃.

⊓ is called the "Square Cap Symbol". It represents meet operations in lattice theory. Its Unicode is U+2293, the LaTeX command is \sqcap, and the HTML entity is ⊓.

⊔ is called the "Square Cup Symbol". It represents join operations in lattice theory. Its Unicode is U+2294, the LaTeX command is \sqcup, and the HTML entity is ⊔.

Set Difference & Complement Symbols

∖ is called the "Set Minus Symbol". It denotes relative complement between sets. Its Unicode is U+2216, the LaTeX command is \setminus, and the HTML entity is ∖.

∁ is called the "Complement Symbol". It denotes absolute complement in a universal set. Its Unicode is U+2201, the LaTeX command is \complement, and the HTML entity is ∁.

Empty Set, Power Set & Cardinality Symbols

∅ is called the "Empty Set Symbol". It represents a set with no elements. Its Unicode is U+2205, the LaTeX command is \varnothing, and the HTML entity is ∅.

℘ is called the "Power Set Symbol". It denotes the set of all subsets of a given set. Its Unicode is U+2118, the LaTeX command is \wp, and the HTML entity is ℘.

ℵ is called the "Aleph Symbol". It represents infinite cardinal numbers. Its Unicode is U+2135, the LaTeX command is \aleph, and the HTML entity is ℵ.

ℶ is called the "Beth Symbol". It represents another sequence of infinite cardinals. Its Unicode is U+2136, the LaTeX command is \beth, and the HTML entity is ℶ.

Topology & Differential Operator Symbols

∂ is called the "Partial Symbol". It denotes set boundaries or partial derivatives. Its Unicode is U+2202, the LaTeX command is \partial, and the HTML entity is ∂.

∘ is called the "Function Composition Symbol". It denotes the composition of functions. Its Unicode is U+2218, the LaTeX command is \circ, and the HTML entity is ∘.

∆ is called the "Delta Symbol". It represents Laplacian or difference operators. Its Unicode is U+2206, the LaTeX command is \Delta, and the HTML entity is Δ.

∇ is called the "Nabla Symbol". It represents gradient, divergence, or curl operators. Its Unicode is U+2207, the LaTeX command is \nabla, and the HTML entity is ∇.

∎ is called the "QED Symbol". It marks the end of a mathematical proof. Its Unicode is U+220E, the LaTeX command is \blacksquare, and the HTML entity is ∆.

Usage Guidelines

For clear and standard mathematical writing, use ⊆ and ⊊ to avoid ambiguity with subset notation. Use \setminus for set difference in LaTeX. Always use mathematical symbols like ∅ instead of alphabetic lookalikes. For large operators, use \bigcap and \bigcup for proper formatting. Load the amssymb package in LaTeX for full symbol support.

Tips

Click any symbol card to copy its Unicode, LaTeX, or HTML code with one click. You can also copy SVG vectors or download high-resolution transparent PNGs for presentations and design work. For academic papers, always use LaTeX commands for professional typography.