This is the 717th most frequent Romanian word.
oficială
"Oficială" means "official" in English.
Here, 'oficială' is used as an adjective describing the formal nature of the ceremony.
Ceremonia a fost foarte oficială.
The ceremony was very official.
'Oficială' here serves as an adjective denoting the building's status as officially designated for city hall functions.
Aceasta este clădirea oficială a primăriei.
This is the official building of the city hall.
In this sentence, 'oficială' characterizes the statement as being formal and issued by authority.