The Free On-line Dictionary of Computing (30 December 2018):

Kleene star
Kleene closure

    (Or "Kleene closure", named after Stephen Kleene) The
   postfix "*" operator used in regular expressions,
   Extended Backus-Naur Form and similar formalisms to specify
   a match for zero or more occurrences of the preceding
   expression.  For example, the regular expression "be*t" would
   match the string "bt", "bet", "beet", "beeeeet", and so on.

   (2000-07-26)