actually,

as per dictionary.com:

com·mon·wealth

1. The people of a nation or state; the body politic.
2. A nation or state governed by the people; a republic.

3. Commonwealth

Used to refer to some U.S. states, namely, Kentucky,Massachusetts, Pennsylvania, and Virginia.

Used to refer to a self-governing, autonomous political unit voluntarily associated with the United States, namely, Puerto Rico and the Northern Mariana Islands.

source(cuz i know how picky we on GC are about copyrights):

The American Heritage® Dictionary of the English Language, Fourth Edition
Copyright © 2000 by Houghton Mifflin Company.

Kitso
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