The term “debutante” was not used until 1817 to describe a young lady making her come-out in society, which included a formal court presentation of curtsying to the queen, as well as attending balls and parties for the first time.

Before this, the word referenced actresses in their first performance. Given its use for the stage, it would have been vulgar and inappropriate to use in reference to a young lady. It was not used until late Regency, still making it of Georgian era origin, but only just.

The tradition of ladies making a formal come-out in society was exclusive to aristocratic women with an aristocratic sponsor. Who could make a come-out widened as the tradition became more popular, but it would remain restricted to those who could afford the costs and those of good family lineage.

The origins go back to Elizabeth I. Young women were presented so she could choose her ladies-in-waiting. The tradition as we know it began not only in the Georgian era but specifically with King Georgie III’s reign.

While we're only looking at the term here, you might find this article interesting as to what coming out in society entailed:

Jane Austen UK: Exploring the Regency Debutante