A binary operator symbol showing a circled asterisk, commonly used to denote convolution or specialized product operations in algebra.
Examples
Convolution operator in signal processing
f(t) \circledast g(t) = \int_{-\infty}^{\infty} f(\tau)g(t-\tau)d\tau
Binary operation in abstract algebra
(G, \circledast) \text{ is a group under the operation } \circledast
Matrix operation notation
A \circledast B = \sum_{i,j} a_{ij}b_{ij}