“The Arabic word ramadun refers to the heat of the sun. In Ramadan, a person restrains themselves from food and drink, and all other physical pleasures. Further, an individual develops within themselves a burning passion and fervour to fulfil the commandments of Allah Almighty. Therefore, spiritual and physical warmth and heat constitute the Arabic word known in dual form as ramadan. It is my view that those lexicographers who suggest that the word ramadan has its etymological roots in the fact that this was a month of heat are incorrect because this is no distinguishing factor in Arabia. Spiritual ‘heat’ refers to spiritual fervour and joy, and religious zeal. The word ramadun also alludes to that heat which causes rocks and the like to become heated.”
(Malfuzat [English], Vol. 1, p. 217)