キャステリャMeanings1nounCastilianRefers to the historical region of Castile in Spain, or its people and language. Often encountered in historical or cultural contexts.キャステリャ王おう国こくは中ちゅう世せいスペインで重じゅう要ような役やく割わりを果はたした。The Kingdom of Castile played an important role in medieval Spain.