The usual masculine Spanish term for a boy’s 15th-birthday celebration is quinceañero.
Quinceañera is the feminine form associated with a girl, while quinceañero is the masculine form. Both words derive from quince, meaning fifteen, and describe a fifteenth-birthday coming-of-age celebration. The masculine version is less widely encountered in English-language discussions because the traditional event has historically been more strongly associated with girls.
A quinceañero can use many of the same elements found in a quinceañera: family ceremonies, formal clothing, music, dancing, a reception, and symbolic recognition of the birthday. The exact program depends on the family and community.
The distinction is grammatical as well as cultural. Spanish nouns and adjectives often mark gender through endings such as -a and -o. That is why changing the final vowel changes the conventional term for the celebrant.