muppet
noun /ˈmʌpɪt/
  /ˈmʌpɪt/
(British English, informal)- a stupid person
- He’s a muppet.
 - You’re ruining it, you muppet!
 
Word Origin1990s: from Muppet, the generic name given to various puppets and marionettes created by Jim Henson (1936–90) for the children's television programmes Sesame Street and The Muppet Show.