Google follows the U.S. Geographic Names Information System (GNIS), which formally changed the name for 'Lake Ontario' to 'Lake America' in the United States, according to Google's announcement about the change, posted Saturday: "Since we update Google Maps to reflect name changes in official government sources, which is GNIS for the U.S., people using Maps in the U.S. will see 'Lake America,' those in Canada will continue to see 'Lake Ontario,' and those outside of the U.S. and Canada will see both names. These updates follow our long-standing policy for bodies of water with names that vary from country to country, and are starting to roll out now."
https://www.404media.co/google-maps-lake-america-lake-ontario-name-change