0 a person who knocks on someone's door for an invented reason and then enters theirhis or her house in order to steal things:
A so-called “Knock-Knock” burglar pleaded no contest today to burglarizing two San Fernando Valley homes.
Typically known as “knock-knock” burglars, these crews, often formed by gang members, utilize high-end luxury vehicles to blend into middle class and affluent neighbourhoods where they break into homes and businesses.
The apparent knock-knock burglar smashed a sliding glass door and searched through cabinets and drawers.