The asterisk , also called a "star," is used for a number of different purposed in mathematics. The most common usage is to denote multiplication so, for example, .

When used as a superscript, the asterisk is commonly voiced "-star." A raised asterisk is used to denote the adjoint , or sometimes the complex conjugate.

A doubled asterisk
is used in the Wolfram Language to
denote noncommutative multiplication.
However, in `FORTRAN`, a doubled asterisk denotes exponentiation (Calderbank
1989, p. 29).