Rebracketing

Rebracketing (also known as juncture loss, junctural metanalysis, false splitting, false separation, faulty separation, misdivision, or refactorization) is a process in historical linguistics where a word originally derived from one source is broken down or bracketed into a different set of factors. It is a form of folk etymology, where the new factors may appear meaningful (e.g. hamburger taken to mean a burger with ham), or may seem to be the result of valid morphological processes.