Spaghetti code is a pejorative term for source code that has a complex and tangled control structure, especially one using many GOTOs, exceptions, threads, or other "unstructured" branching constructs. It is named such because program flow is conceptually like a bowl of spaghetti, i.e. twisted and tangled.
pejorative
a word or expression that is pejorative is used to show disapproval or to insult someone
http://en.wikipedia.org/wiki/Spaghetti_code