Lawful Permanent Resident (LPR)

Any person not a citizen of the United States who is residing the in the U.S. under legally recognized and lawfully recorded permanent residence as an immigrant. Also known as "Permanent Resident Alien," "Resident Alien Permit Holder," and "Green Card Holder."

Source: U.S. Citizenship and Immigration Services

A person who has immigrated legally but is not an American citizen.  This person has been admitted to the U.S. as an immigrant and has a Permanent Resident Card, Form I-551 also known as green card.  It is a wallet-sized card showing that the person is a lawful permanent resident (immigrant) in the United States.  This person is also called a legal permanent resident, a green card holder, a permanent resident alien, a legal permanent resident alien (LPRA) and resident alien permit holder.

Source: U.S. Department of State.