“Novinha” is a term that appears in funk music lyrics, and also in sexual content. It is used for young girls, similar to how the term teen is used in English. It does not necessarily mean underage, but that depends on the context.
It is the diminutive of “nova“.
“Oh novinha, eu quero te ver contente Não abandona o piru da gente Que no Helipa, confesso, tu tem moral Vinha aqui na favela” (from Ôh Novinha, by MC Don Juan)
An object that despite its age does not show any wear and tear.