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).