In short, the term ‘Hindu’ derives its origin from the Sanskrit word ‘Sindhu’ that watered through the northwestern parts of the region and which now encapsulates the countries of India, Pakistan, Bangladesh and Nepal. the northwest was the doorway to India for conquerors seeking to amass this land. When the foreigners chanced upon the inhabitants of this place who resided close to the banks of the Sindhu — or as it is know today, the Indus — they named the whole country after it; ‘India’ which resembles the Greek term for it.
The syllable ‘s’ transmutes to ‘h’ in Persian (present-day Iranian) and so came the word ‘Hindu’ therefrom. Consequently, India was called ‘Al-Hind’ by Persians and Arabs. It may be of service to note here that the first Iranian inscriptions make reference to ‘Hindu’ as a district on the Indus. It neither alluded to a religion nor a community. It was only later in the 14th and 15th centuries that it came to denote the followers of a particular religion.