What's in a name? President-elect Donald Trump held a press conference on Tuesday at his Mar-a-Lago resort in Florida where he rambled off many statements — but one that stuck out was that he plans to rename the Gulf of Mexico the "Gulf of America."

"Because we do most of the work there, and it's ours...we're going to be changing the name of the Gulf of Mexico to the Gulf of America. Gulf of America," he said. "What a beautiful name. And it's appropriate."

Shortly after the remarks, Rep. Marjorie Taylor Greene from (R-Ga.) posted to her social media that she would introduce a bill "ASAP" to make the name change happen.

The Gulf of Mexico has been depicted with that name for more than four centuries, an original determination believed to have been taken from the Native American city of “Mexico" after it was first noted on maps during the Christopher Columbus era of exploration.

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The large body of water stretches along approximately 1,631 miles of the United States southeastern coastline consisting of Florida, Alabama, Mississippi, Louisiana and Texas.

Approximately 1,743 miles of Mexico's coastline borders the gulf, as well as some real estate in the island country of Cuba.

Often referred to as the "third coast of the U.S." and the "Mediterranean of the Americas," the Gulf of Mexico is rich in boundless ways. From oil and mineral resources to marine life to critical shipping ports to tourism on what some may argue are the most beautiful beaches in the world.

Like all maritime laws, who owns what in the gulf is complicated and exercised through many years of treaties. But, for the most part, the United States' "exclusive economic zone" gives us jurisdiction up to 200 miles offshore in the Gulf of Mexico.

The Submerged Lands Act of 1953 gives all states three nautical miles of jurisdiction off their coasts, with the exception of Texas and Florida's gulf coasts which get nine nautical miles.

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So why is Trump bringing up a name change now? He didn't elaborate, but it's no secret that the president-elect has long clashed with Mexico.

His statements on the name change in Tuesday's presser came right after saying, "We help Mexico a lot. They're essentially run by the cartels. And can't let that happen. Mexico's really in trouble. A lot of trouble. Very dangerous place."

And he's not the first one to bring this up this idea. In 2012, a member of the Mississippi Legislature proposed a bill to rename portions of the gulf that touch that state's beaches “Gulf of America,” a move the bill author later referred to as a “joke.” That bill, which was referred to a committee, did not pass.

Changing the name would not be a unilateral decision, and other countries don't have to go along.

The International Hydrographic Organization — of which both the United States and Mexico are members — works to ensure all the world’s seas, oceans and navigable waters are surveyed and charted uniformly, and also names some of them. There are instances where countries refer to the same body of water or landmarks by different names in their own documentation.

It can be easier when a landmark or body of water is within a country's boundaries. In 2015, then-President Barack Obama approved an order from the Department of Interior to rename Mount McKinley — the highest peak in North America — to Denali, a move that Trump has also said he wants to reverse.