What is 'Metanalysis' (or Rebracketing) in historical linguistics?

1. ক
   A change in the boundary of morphemes within a word
   
2. খ
   The loss of a phoneme at the end of a word
   
3. গ
   The borrowing of a grammatical structure
   
4. ঘ
   The shift of stress in a polysyllabic word