Wedding dress
A dress worn once at a wedding — a garment that carries a single day's whole occasion in its cloth.
A wedding dress in a dream is the dream's image of a garment built to carry a single day's whole occasion in its cloth. The dress is too elaborate for any ordinary use; the elaboration is the point. The dream brings the wedding dress when something in your life — a public commitment, an event that organises a whole community around a single decision — is being marked by clothing made for that occasion alone. A wedding dress worn at the wedding it was made for is the dream affirming the right joining of occasion and form. A wedding dress in a closet decades later, never worn again, is the dream noting that the dress's purpose was specific and is finished, and the cloth has become a remembered, not a current, thing.