The asterisk (*) is the Truncation character, used to replace one or more characters. The truncation character can be used at the end (right-hand truncation), or in the middle of a word.The standard expansion of the asterisk character (*) is five characters, though you can specify longer.

Example:
“Intertextuality” is six characters longer than the first stem “intertext” while it is only five characters longer than the stem “intertextu”