You’ve heard it in speeches and seen it on government documents: Massachusetts is not a state. It’s a commonwealth.

But what does that actually mean?

Massachusetts is one of four commonwealths in the nation, the others being Virginia, Pennsylvania and Kentucky.

In Massachusetts, the name goes back to founding father and Massachusetts resident John Adams, who wrote the Massachusetts constitution, drafted in 1780. An earlier draft of the Massachusetts constitution referred to it as the state of Massachusetts Bay.

But when Adams wrote his constitution, he said: We are the Commonwealth of Massachusetts.

Why he used that word has been lost to time, but Sara Martin, the editor in chief of the Adams Family Papers Collection at the Massachusetts Historical Society, had a few possible clues as to why.

One is that the word commonwealth sounds lofty. Adams would use state and commonwealth interchangeably when talking about Massachusetts, but it seems that when he used the word commonwealth it was for fancier things.

Another clue is that state is a very general term: A state can have any kind of government. It could be a democracy, it could be a monarchy, it could be an aristocracy. Other Adams writings indicate that he felt the word commonwealth was the best direct translation of the Latin word republic. We have the sense that when he uses commonwealth, he's saying, "this isn't just any state that can have any kind of government, it's specifically a republic."

Furthermore, there is the competitive streak that we know Adams had. By the time Massachusetts deemed itself a commonwealth, both Pennsylvania and Virginia had already taken on the designation. Perhaps Adams was saying, "let's make sure we know that Massachusetts is on the same footing as Virginia."

Practically speaking, it’s really a distinction without a difference. It makes no legal difference and changes nothing about government structures or its relationship with the federal government. It just might sound exalted, when recapping yesterday's election results, to say 'Maura Healey is the governor-elect of the Commonwealth of Massachusetts.'

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