This is the 5401st most frequent Portuguese word.
secretas
"Secretas" means "secret" or "hidden" in English.
The word 'secretas' is used to describe the rooms, giving them the attribute of being hidden or not commonly known based on the noun 'salas'.
As salas secretas do castelo guardam tesouros antigos.
The secret rooms of the castle hold ancient treasures.
Here, 'secretas' refers to skills, implying these are undisclosed or unknown to others based on the noun 'habilidades'.
Ela tem habilidades secretas que ninguém conhece.
She has secret skills that nobody knows about.
The term 'secretos' (masculine form) is applied to 'documentos', specifying that they are confidential or restricted in access, utilizing the masculine plural form.