I never read any such thing but there are many theories about this name and ibne batutah and Britannica encyclopedia are saying this and they are not Pakistani sources or text books
The origins of the name "Hindu Kush" are
are uncertain, with multiple theories being
propounded different scholars and writers. In the time of
Alexander the Great, the Hindu Kush range was referred to as the
Caucasus Indicus or the "Caucasus of the
Indus" (as opposed to the
Greater Caucasus range between the
Caspian and
Black Seas), and some past authors have considered this as a possible derivation of the name "Hindu Kush". However, many other theories have been propounded by different scholars and writers for the origins of the modern name
Hindu Kush.
Hindū Kūh (ھندوکوه) and
Kūh-e Hind(کوهِ ھند) are usually applied to the entire range separating the basins of the
Kabul and
Helmand rivers from that of the
Amu River(ancient
Oxus), or more specifically, to that part of the range lying northwest of the Afghan capital
Kabul.
Sanskrit documents refer to the Hindu Kush as
Pāriyātra Parvata(पारियात्र पर्वत).
[3]
The mountain range was called
"Paropamisadae" by Hellenic Greeks in the late first millennium BC.
[4]
Other sources state that the term "Hindu Kush" originally applied only to the peak in the area of the
Kushan Pass, which had become a center of the
Kushan Empire by the 1st century AD.
The Persian-English dictionary
[5] indicates that the word 'koš' [kʰoʃ] is derived from the verb ('koštan' کشتن [kʰoʃˈt̪ʰæn]), meaning to kill. Although the derivation is only a possible one, some authors have proposed the meaning 'Kills the Hindu' for "Hindu Kush", a derivation that is reproduced in
Encyclopedia Americana:
The name Hindu Kush means literally 'Kills the Hindu', a reminder of the days when Indian slaves from the Indian subcontinent died in the harsh weather typical of the Afghan mountains while being transported to Central Asia.
[6]
The World Book Encyclopedia states that "the name Kush, .. means Death".
[7] While Encyclopædia Britannica says 'The name Hindu Kush first appears in 1333 AD in the writings of
Ibn Battutah, the medieval
Berbertraveller, who said the name meant 'Hindu Killer', a meaning still given by Afghan mountain dwellers who are traditional enemies of Indian plainsmen.
[8]
The word
Koh or
Kuh means "mountain" in some local language Khowar. According to Nigel Allan,
Hindu Kush meant both "mountains of India" and "sparkling snows of India", as he notes, from a Central Asian perspective.
[9] Furthermore, some believe it to be the name derived from the rule of the Hindu god
Rama's son,
Kusha, who ruled in Kasur, in present day Punjab, Pakistan.
SOURCE: WIKIPEDIA