This is the 68th most frequent Romanian word.
nou
"Nou" in Romanian means "new" in English.
Here, "nou" is used as an adjective qualifying the noun "telefon" to describe it as new.
Am cumpărat un telefon nou.
I bought a new phone.
In this sentence, "nou" is used to describe "capitol" (chapter), implying something that has just started or was previously nonexistent.
Acesta este începutul unui nou capitol.
This is the beginning of a new chapter.
Here, "nou" is used to describe "stil" (style) as being fresh, modern, or different than previous styles.