ominus

Represents a binary operation denoted by a circle with a minus sign inside, commonly used in mathematical notation.

Overview

Appears frequently in abstract algebra and mathematical logic to denote specialized subtraction or difference operations. This symbol is particularly useful in:

Group theory and ring theory for describing inverse operations
Set theory for symmetric difference operations
Mathematical logic for specialized binary operations
Formal mathematical notation where a circled minus is needed to distinguish from standard subtraction

Examples

Representing the symmetric difference of sets A and B.

A \ominus B = (A \setminus B) \cup (B \setminus A)

A \ominus B = (A \setminus B) \cup (B \setminus A)

Denoting the inverse operation in a group with circle notation.

x \ominus y = z

x \ominus y = z

Expressing binary subtraction in modular arithmetic.

5 \ominus 3 \equiv 2 \pmod{8}

5 \ominus 3 \equiv 2 \pmod{8}