Adulto (en. Adult)
/aˈdul.to/
Slang Meanings
An adult who acts irresponsibly.
That guy is a man-child; he doesn't take on his responsibilities.
Ese tipo es un adulto niño, no asume sus responsabilidades.
An older person who still behaves like a young person.
He is an adult, but still has a youthful mentality.
Es un adulto, pero sigue teniendo una mentalidad juvenil.