This is the 7th most frequent French word.
une
The French word "une" is the feminine singular indefinite article, meaning "a" or "an" in English.
In this sentence, 'une' is used as the feminine singular indefinite article, meaning 'a' in English.
Elle a acheté une robe hier.
She bought a dress yesterday.
Here, 'une' is used in the phrase 'une fois' meaning 'once', showing temporal context.
Une fois arrivée, elle nous a téléphoné.
Once she arrived, she called us.
In this example, 'une' functions as the feminine singular numeral determiner, meaning 'one' in English.