What does the word Navajo mean?

'enemies with the cultivated lands in arroyos'

The Word Navajo is derived from Spanish hearing of a Tewa Indian Word "navahu'u" or "na-ba-hu-u " meaning wide or river bottom fields. The Spanish were trying to tell apart the different Apache related groups.

"Apache " is thought to come from Zuni for "enemy". The Tewa were saying that the people over towards where Farmington NM is now were the Apache group who grew corn in river bottom land. The others ate Mescal- Mescalero Apache, or made little baskets- Jicarilla Apache. They were "Navajo de Apache".

The idea that it means knife or thief has been thoroughly debunked.