Legend behind name Manas

Manas has a history and many legends. Many folktales relates with name Manas. I hereby describing one of thought as follows:

According to a school of thought, the river Manas actually has a Bhutanese name as “DANG-ME-CHU” and “MANG-DE-CHU” meeting at a confluence point called Panbang, a small sub divisional HQ inside Bhutan to become Manas River that is upstream within Bhutan. Though lost in antiquity the name “Manah” (not Manas as is usually known) is derived from Assamese word “maan”, meaning the Burmese army, popularly known as Maan, who raided Assam three times spreading terror. As the river was the western limit of Burmese advance, the challenge came from across saying: maan+ah = manah; meaning “Maan you come if you dare”.

On the contrary, the other school of thought offers the view that the name “manas” gets its name after the serpent Goddess “manasa” (Durga).
(Source- Management Plan of Manas Tiger Reserve, Assam)

River Manas with Bhutan Hill