Which is the most widely spoken indigenous language of North America?

The most widely spoken indigenous language of North America is Navajo, spoken by the Navajo people primarily in the southwestern United States. It has approximately 170,000 speakers, making it the largest Native American language in the country. Navajo is a tonal language with a rich vocabulary and complex grammatical structure. It has been used as a code during wartime due to its unique features and difficulty for non-native speakers to understand.