The Spanish word for “fifteen” forming the first part of “quinceañera” is quince.
The term quinceañera is built from quince and a feminine form connected with the celebrant. Its literal connection to fifteen explains why the tradition centers on a girl’s fifteenth birthday. The ñ in quinceañera is a distinct Spanish letter and is part of the standard spelling.
The word is often used in two related ways: for the young woman being honored and for the celebration itself. Context usually makes the meaning clear. English-language communities commonly retain the Spanish term even when the event is conducted partly or entirely in English.
Quince is not the Spanish word for fifth; that word is quinto. This distinction matters because the celebration concerns fifteen, not the fifth birthday or fifth year.