While the RAE recommends calling the language Spanish, it recognizes that Castilian is a synonym of Spanish. [1] My personal experience also corroborates this.

While the RAE recommends calling the language Spanish, it recognizes that Castilian is a synonym of Spanish. [1] My personal experience also corroborates this. In common usage, Castilian is the same language as Spanish and in fact I hear people from Spain refer to the language as Castilian, even when talking about the language as spoken in Latin America, regardless of the Academy's prescription. [1] https://www.rae.es/dpd/espa%2525C3%2525B1ol https://www.rae.es/dpd/espa%2525C3%2525B1ol