This Grace Kelly fan-art contains
robe de dîner, formel, robe de soirée, formelle, robe, robe de cocktail, and gaine.
There might also be
robe, demoiselle d'honneur, demoiselle d’honneur, formalwear, eveningwear, robe de soirée, vêtements de soirée, soir, and vetu.