Rangpur, city in Bangladesh, not to be confused with "Rampur", the names of a city and a former state in India. The name of the variety of citrus apparently derives from the name of Rangpur, the city.
Rangpurs, also known as lemanderins, are a hybrid between the mandarin orange and the lemon. It is a citrus fruit of the species citrus limonia with a very acidic taste and an orange peel.