Nuño (Spanish) or Nunyo (Catalan) is a masculine given name of Latin origin (Nunnus, Nonnus, Nunus, Nunno and so on).
Its patronymic is Núñez (Latin: Nunni).
Already in the Middle Ages the name was being confused with the similar but distinct name Munio.
It could come from late Latin nonnus, meaning 'tutor', later 'monk'.
The classicist Iiro Kajanto proposed a Celtic origin, since the name is mainly found in formerly Celtic-speaking parts of Spain.