(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)