Definition of commonwealth
1 : a nation, state, or other political unit: such as
a : one founded on law and united by compact or tacit agreement of the people for the common good
b : one in which supreme authority is vested in the people
c : republic
2 : a state of the U.S.
—used officially of Kentucky, Massachusetts, Pennsylvania, and Virginia
3 often capitalized : a political unit having local autonomy but voluntarily united with the U.S.
—used officially of Puerto Rico and of the Northern Mariana Islands
4 often capitalized : an association of self-governing autonomous states more or less loosely associated in a common allegiance (as to the British crown)
5 capitalized
a : the English state from the death of Charles I in 1649 to the Restoration in 1660
6 capitalized : a federal union of constituent states
—used officially of Australia
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Time Traveler for commonwealth
The first known use of commonwealth was in the 15th century
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