It is peculiar to see the confusion that for many foreigners and even for some Spaniards supposes when they have to denominate the language “Spanish"(español) or "Castilian" (castellano). In very few languages exists a similar doubt, but in Spain it is so because of historical causes.

The official language that is also spoken in Spain is called Castilian or “castellano”, being the name of the linguistic community that spoke this romanic modality in medieval times: Castile. There is some controversies about the language denomination; the Spanish term is relatively recent and it is not accepted by many bilingual speakers of the Spanish State, because they understand that Spanish includes the terms Valencian, Galician, Catalan and Basque, languages of official consideration too in the territory of his respective regions; those bilingual speakers are who propose to return to the older denomination of this language, Castilian understood like ' language of Castile.

In Latin America has been conserved this denomination and they do not have special difficulty to understand the terms Castilian and Spanish as synonymous. In first documents after the foundation of the Real Spanish Academy, their members used by agreement the denomination of Spanish language. Who better has studied this complex question has been Amado Alonso in a book titled Castellano, español, idioma nacional. Historia espiritual de tres nombres (1943).

To give up the Spanish term would suppose the difficulty to recognize the official nature of a language that has been so opened to welcome the different influences and tolerances that have contributed to their condition.

In the other hand, as much right have Spaniards to denominate Castilian to its language as the Argentineans, Venezuelans, Mexican, or Panamanians to describe it as Argentinean, Venezuelan, Mexican or Panamanian, to mention some examples. It could mean the first step for the fragmentation of a language, that occupies the third place in the languages of the world by speakers number. In Spain it is spoken Gallego and Catalan, languages of Romanesque origin, and the Basque, of debated origin.