The common shortened name for a quinceañera celebration in English-language usage is “quince.”
In conversation, families and communities often shorten quinceañera or quince años to quince. The short form can refer to the party, the event planning process, or the celebration as a whole. It is especially common in communities where Spanish and English are used together.
The word quince is also the Spanish number fifteen, so context determines whether it means the number or the celebration. In a phrase such as “her quince,” it normally means her quinceañera event. In ordinary Spanish, quince by itself simply means fifteen.
The shortened term does not replace the longer word in every setting. Formal invitations, religious programs, and explanatory writing may use quinceañera or quince años so that readers unfamiliar with the tradition understand the occasion.