The Free On-line Dictionary of Computing (30 December 2018):
explicit type conversion
(Or "cast" in C and elsewhere). A programming
construct (syntax) to specify that an expression's value
should be converted to a different type.
For example, in C, to convert an integer (usually 32 bits)
to a char (usually 8 bits) we might write:
int i = 42;
char *p = &buf;
*p = (char) i;
The expression "(char)" (called a "cast") converts i's value
to char type. Casts (including this one) are often not
strictly necessary, due to automatic coercions performed by
the compiler, but can be used to make the conversion obvious
and to avoid warning messages.