The light dressed up for the costume party as a feather. It is a common English joke that plays on the idiom, light as a feather, notes The Free Dictionary.
The idiom, light as a feather, is used to refer to an object as extremely light or without significant weight. Idioms are generally language specific; and, they do not carry the same implied meaning when translated into other languages.
The phrase "light as a feather" appears repeatedly in classic English literature. Dickens' character Ebenezer Scrooge proclaims, "I am as light as a feather," in the holiday classic, "A Christmas Carol," after he awakes from his ghostly visitors.