Who gave the Amazon river its name and why?

Why is the name of the Amazon River Amazon and who gave this name to that river and for what reason? Here is the description:

Francisco de Orellana is a Spanish explorer and conquistador born in 1511 in the "village" of Trujillo, Cáceres, Spain.

Francisco de Orellana Bejarano Pizarro y Torres de Altamirano (1511 – November 1546) was a Spanish explorer and conquistador. In one of the most improbably successful voyages in known history, Orellana managed to sail the length of the Amazon, arriving at the river's mouth on 24 August 1542. He and his party sailed along the Atlantic coast until reaching Cubagua Island, near the coast of Venezuela.

It is said that he gained his fame today by conquering one of the beautiful cities of Ecuador, Guayaquil, but I think he gained this fame by the name he gave to the river he fought. Amazon River…

The Amazon River in South America is the largest river by discharge volume of water in the world, and the disputed longest river system in the world in comparison to the Nile.

Francisco de Orellana led an expedition along the Amazon River. Reaching the mouth of the river in August 1542, Orellana was attacked by the long-haired Icamiaba Indians. Because she described the event as an "attack by female warriors" in her notes, this river was named "Amazon", meaning "Female Warrior".

Francisco de Orellana died in Brazil in 1546, at the age of about 35.