A derogatory term for the Commonwealth of Massachusetts. Usually used by residents of said state, as a way of complaining about the taxes. I am not sure if the tax burden in MA are actually higher than average, but when compared to New Hampshire which has no state income tax, at all, it does seem high.

It is a very interesting name, given that one of the most famous historic figures from MA was Henry David Thoreau, who was jailed for not paying taxes more than once. His essay Civil Disobedience clearly states his position on this.

It should be noted that usage of this term peaked about 6-10 years ago and has been in decline recently.