This is the 3534th most frequent Portuguese word.
possuíam
"Possuíam" means "they possessed" or "they had."
In this sentence, 'possuíam' is the third-person plural imperfect indicative form of the verb 'possuir', which means 'to own'. It indicates a historical or past possession of lands by families.
Antigamente, muitas famílias possuíam grandes terras agrícolas.
In the past, many families owned large agricultural lands.
'Possuíam' here implies the individuals had control or ownership over unique skills in past time.
Eles possuíam habilidades únicas que os tornaram especiais.
They possessed unique skills that made them special.
This usage of 'possuíam' suggests that ancient civilizations retained or had ownership of advanced architectural knowledge in the past.