Although the title is derived from the same root as "infant", in Romance languages the term may be more broadly interpreted to mean "child" (cfr. French enfants de France), and historically indicated that the infante or infanta was the child of the nation's monarch.
Like the enfants de France, all infantes in the various Iberian kingdoms were princes of the blood royal, although since 1987 the Spanish sovereign may confer the infantado upon a person (e.g., the spouse of an infante or infanta) who is not of royal descent.
Infante had no feminine form at first in Portugal and may be compared to the infanções of the lower Portuguese nobility, who were also cadets of their families with no prospect of inheriting the main possessions of the noble families to which they belonged, being distinguished in law by some prerogatives, but little patrimony.
Later, the word infanta emerged in Portugal as a feminised form applied to Portuguese princesses after the 16th and 17th centuries. Also, after Edward, King of Portugal, in the 15th century, the heir apparent and his eldest son, or daughter if there was no son, came to be styled "prince" or "princess". The first prince in Portugal was the future Afonso V, his eldest son, maybe adopting the French royal style by an English influence imported by Philippa of Lancaster's retinue.
After the accession of the House of Braganza to the throne, the honorific of "Most Serene" (Sereníssimo) was prefixed to the title of infante (Sereníssima for an infanta), since the complete appellation of this dynasty was "Most Serene House of Braganza" (Sereníssima Casa de Bragança), a style granted by the Pope. The style, however, does not seem to have been used with the title of Prince Royal.
In current use the title is often accorded in Portugal (presently a republic) to close relatives of Duarte Pio, Duke of Braganza, head of the Portuguese Royal House:
In the Royal Family the dynastic children of the monarch and of the heir apparent are entitled to the designation and rank of infante with the style of Royal Highness (infantes by birth). A second category of infantes may be granted that title by Royal Decree (infantes by grace), but only bear the style of Highness. Previously, the title and rank of infante of Spain was often granted to relatives and in-laws of Spain's monarchs, but unlike those created under the 1987 decree, their dynastic wives were automatically infantas and bearers of the title were Royal Highnesses.
The generations indicate descent from Carlos I, under whom the crowns of Castile and Aragon were united, forming the Kingdom of Spain. Previously, the title Infante had been largely used in the different realms.