Costume (noun)

1. An outfit worn by an actor on stage or a person taking part in a costume event.
2. A set of clothes worn for a particular occasion or purpose.
3. The style of dress, including clothing, accessories, and hairstyles, typical of a particular period, place, or group.

Origin:

From old french costume, from latin consuetudinem ("custom, habi.t")

Examples:

1. The actor was wearing a costume for the play.
2. The costume party was a lot of fun.
3. The children were dressed in costumes for Halloween.
4. The costume design was based on the 18th century fashion.
5. The dancers were wearing traditional costumes from their country.