It is believed that Niagara is a derivative of the Iroquoian word, “Onguiaahra”, which was anglicized by missionaries. The name appears on maps as early as 1641.The generally accepted meaning is, “The Strait”. Some think it was derived from the narrow waterway that flows north from Lakes Erie to Lake Ontario.Early maps do not refer to the Niagara River but the Niagara Strait which is more correct.Others believe the word Niagara is taken from another native word meaning, “Thundering Waters”. Regardless, wherever the word comes from, Niagara is another word for anything powerful.arly maps do not refer to the Niagara River but the Niagara Strait which is more correct. Others believe the word Niagara is taken from another native word meaning, “Thundering Waters”. Regardless, wherever the word comes from, Niagara is another word for anything powerful.