Princess Anne, Duchess of Calabria in the context of "Infante"

Infante (Spanish: [iɱˈfante], Portuguese: [ĩˈfɐ̃tɨ]; f. infanta), also anglicised as "infant" or translated as "prince", is the title and rank given in the Iberian kingdoms of Spain (including the predecessor kingdoms of Aragon, Castile, Navarre, and León) and Portugal to the sons and daughters (infantas) of the king, regardless of age, sometimes with the exception of the heir apparent or heir presumptive to the throne who usually bears a unique princely or ducal title. A woman married to a male infante was accorded the title of infanta if the marriage was dynastically approved (e.g., Princess Alicia of Bourbon-Parma), although since 1987 this is no longer automatically the case in Spain (e.g., Princess Anne d'Orléans). Husbands of born infantas did not obtain the title of infante through marriage (unlike most hereditary titles of Spanish nobility), although they were occasionally elevated to the title de gracia ("by grace") at the sovereign's command.

While the title belonged by right to all sons and daughters of a monarch (even when they ceased to be children of the reigning sovereign), it was also often accorded to sons-in-law and male-line grandchildren of the sovereign (e.g., Prince Ferdinand of Bavaria, Infante Pedro Carlos of Spain and Portugal), sometimes to other agnates of the ruling dynasty (e.g., Infante Enrique, Duke of Seville), and to female-line relatives of the monarch (e.g. Infante Sebastian of Portugal and Spain, Infante Alfonso de Orléans-Borbón).