A boy celebrated at age 15 in the quinceañera tradition is traditionally called a quinceañero.
The Spanish ending -a commonly marks the feminine form, while -o marks the masculine form, so quinceañera and quinceañero distinguish the celebrant. The feminine term is much more widely recognized because the custom historically centered on girls.
A quinceañero celebration can include elements associated with quinceañeras, such as formal clothing, a religious service, family speeches, music, and a court. Practices vary substantially by country, family, religion, and budget.
Quinceañero should not be confused with chambelán, which commonly refers to a male member or escort of the celebrant’s court. Padrino means godfather or sponsor and identifies a supporting role, not the birthday celebrant.