High Quality Content by WIKIPEDIA articles! Rioplatense Spanish (Spanish: español rioplatense, although locally known as castellano rioplatense) is a dialectal variant (or simply, "a dialect"), of the Spanish language which is mainly spoken in the areas in and around the Río de la Plata basin (or River Plate region), between Argentina and Uruguay. The usual word employed to name the Spanish language in this region is castellano (Castilian) and seldom español (Spanish) as in other parts of Latin America. Note that, while the article refers to Rioplatense Spanish as a single dialect, there are distinguishable differences among the varieties spoken in Argentina and in Uruguay, as described below.