The Quinceañera or Quince Años (sometimes represented XV Años, meaning "fifteen years") is, in some Spanish-speaking regions of the Americas, a young woman's celebration of her fifteenth birthday, which is celebrated in a unique and different way from her other birthdays. The closest equivalents to the Quinceañera in the English-speaking world are the sweet sixteen or, in more affluent communities, a debutante ball at the age of eighteen.

This celebration marks the transition from the childhood to womanhood of a Quinceañera. It serves as a way to acknowledge that a young woman has reached maturity.

Some traditions observed in the celebration include the giving and throwing of a quince doll. The display doll signifies the young lady's last doll as a child and the throwing doll, usually a Barbie type, is thrown by the young lady to the other female children in attendance much as the garter is thrown in a wedding. The celebrant is wearing flats, or flat shoes for the celebration but after the inaugural dance the father of the young lady, who is sitting in a chair in the center of the dance floor, removes her flats (girls shoes) and puts her high heels on signifying her becoming a young lady.

Most parties have the girl wear a pink dress (as she is still a girl, never white which equals bride but now other cultures are letting the girl pick a color) and a tiara because she is a princess in God's eyes that night. She holds a court with 14 girls (damas) and 15 boys (chambelanes) which including herself would equal 30 people, or, 15 couples (to represent each year). At the party the court does a waltz and a surprise dance. The girl also dances with her father but first changes from flats to heels to represent the first time she can wear them (the same with makeup). She could also get a doll with the exact same dress she has on to signify that this will be the last doll she ever will receive. In the past the party would show the girl is ready to be married, but now in today's culture it is so the girl can date.

In the Mexican tradition, if the quinceañera is Roman Catholic, the festivities begin with a Thanksgiving Mass (Misa de Acción de Gracias), at which the quinceañera arrives in formal dress (usually of color representing childhood) accompanied by her parents, godparents, a number of maids of honor (damas or primaveras) and chamberlains (chambelanes)(also called escorts) ranging in number anywhere from seven to 15 couples. After the Mass, the younger sisters, female cousins and friends of the quinceañera pass out party favors and the quinceañera leaves her bouquet in an altar to the Virgin Mary.

The Mass is followed by a party either at the quinceañera's home or in a banquet hall leased for the occasion. At the party, the quinceañera dances the traditional first waltz with her father and male relatives. Then her male friend or relative, (also called a chambelan), dances the remaining part of the dance with the birthday girl.

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