This is the 663rd most frequent French word.
officiellement
"Officiellement" means "officially" in English.
The word 'officiellement' here specifies the formal or recognized manner of the announcement.
Elle a officiellement annoncé sa candidature à la présidence.
She officially announced her candidacy for the presidency.
In this sentence, 'officiellement' indicates the legally or formally recognized status of their marriage.
Ils sont officiellement mariés depuis l'année dernière.
They have been officially married since last year.
'Officiellement' is used in this context to indicate the authorized or formal commencement of the store's operation.