Symbols:General/Prime

$x'$
The symbol $'$ is a general indicator of another version of or another type of where the specific version or type that is being described is to be defined.
The symbol $x'$ should technically be voiced x prime, although colloquially referred to as some variant of x dash or x tick or whatever can be devised by the ingenuity of the reader.
The $\LaTeX$ code for $x'$ is x'  or x^{\prime}.