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Colon Equals Symbol

≔ (colon equals) is a math symbol commonly used to define something as equal to an expression.

U+2254

The symbol “≔” is called colon equals. It’s mainly used in mathematical writing to express definitions and formal assignments. Use it when you want a clearer “is defined as” or “assigned to” meaning.

Colon Equals Symbol Meaning

“≔” is known as the colon equals symbol and is used to state that a value or expression is defined to be equal to something else. In many math and logic texts, it appears in definitions (e.g., “let x ≔ …”), emphasizing that the expression becomes the definition of a new object rather than an ordinary equality. You can also use it in pseudocode and specification-style writing to indicate assignment in a more formal way than “=”. When choosing between “=” and “≔”, use “≔” to signal definition/assignment intent, not just a numeric or algebraic equality statement.

Common uses

  • Mathematical definitions: “Let f(x) ≔ …”
  • Formal specification: writing “x ≔ value” for assignments
  • Algorithm pseudocode and steps: indicating an update in a formal style
  • Logic and reasoning documents: defining predicates or variables
  • Technical writing and diagrams: labeling “defined as” relationships

Examples

≔ Colon Equals

  • Let g(x) ≔ x^2 + 1.
  • We define S ≔ {1, 2, 3}.
  • Set n ≔ 10 for this iteration.
  • Let y ≔ (a + b) / 2.
  • In the specification, x ≔ x + 1.

Variations

Ready to copy

Technical codes

UnicodeU+2254
HTML Entity≔
HTML Code≔
CSS\2254

FAQ

What does the Colon Equals symbol mean?

“≔” is known as the colon equals symbol and is used to state that a value or expression is defined to be equal to something else. In many math and logic texts, it appears in definitions (e.g., “let x ≔ …”), emphasizing that the expression becomes the definition of a new object rather than an ordinary equality. You can also use it in pseudocode and specification-style writing to indicate assignment in a more formal way than “=”. When choosing between “=” and “≔”, use “≔” to signal definition/assignment intent, not just a numeric or algebraic equality statement.

What is the name of the “≔” symbol?

It’s commonly called “colon equals” (Unicode name: COLON EQUALS).

Is “≔” the same as the equals sign “=”?

Not exactly. “≔” usually signals definition or formal assignment (“is defined as” or “set to”), while “=” is typically used for general equality.

Where can I use “≔” in writing?

Common places are math definitions (“let x ≔ …”) and specification-style pseudocode to indicate a formal assignment.

How do I copy and paste “≔” reliably?

Copy the character directly from this page. For web or code entry, you can also use its Unicode forms: HTML entity “≔” and Unicode code point “U+2254”.

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