When quinceañera names the celebration rather than the celebrant, its usual English translation is “fifteenth birthday.”
The word is built from quince años, “fifteen years,” and the celebration centers on a girl’s fifteenth birthday. English speakers often retain the Spanish word because it identifies a culturally specific event with religious, family, musical, and ceremonial elements.
The phrase “fifteenth birthday” is accurate but less specific than quinceañera. A quinceañera may include a formal court, a special dress, symbolic gifts, a dance, and sometimes a Catholic Mass. A typical birthday party does not necessarily include those features.
The tradition is associated especially with Latin American communities and their diasporas, but practices differ widely. It is also distinct from the U.S. “sweet sixteen,” which centers on age sixteen and developed within a different cultural context.