Its name means 'Indian date' in Arabic, which is how medieval Arab traders described the sticky, dark tamarind pulp, and it's the origin of the English word tamarind.
Tamr hindi is a tart, sweetened tamarind drink made by soaking and straining tamarind pulp with sugar and water, served ice cold. In Jordan it's sold by street vendors from large urns, especially in the evenings during Ramadan and through hot summer months.