This is the 4064th most frequent Spanish word.
darío
"Darío" is a male given name in Spanish.
In this sentence, 'Darío' is used as a proper noun referring to a person's name.
Darío es mi mejor amigo.
Darío is my best friend.
Here, 'Darío' refers to a historical figure, namely Darius I, therefore a proper noun also.
El libro comenta la era de Darío I en Persia.
The book discusses the era of Darius I in Persia.
In this case, 'darío' is treated as a term or concept whose meaning might depend on specific usage or context.