The word "Indus" and the cognate word "Hindu" are derived from "Sapta Sindhu" (Sanskrit for "seven rivers") for the region is ancient. The Ancient Greeks used the word "Indós"; "Hinduš" was Old Persian; "Sindhu" in Sanskrit. Modern languages on the sub-continent use either "Sindh" (modern Sindhi) or "Sindhu" (ancient Sanskrit) or very similar words. The river's region's name came to be the name of the country India.