ICING

[esp. US] frosting [noun] [U]Icing is a sweet mixture of sugar, water and the colourless part of eggs or other substances, used to cover cakes.The cake had 'Happy Birthday' written on it in chocolate icing.See picture: CakesIf something is the icing on the cake it is (disapproving) an unnecessary thing that has been added to something that is already satisfactory, or (approving) an unexpected extra good thing when you have already had good luck.Having a fancy book cover is expensive and unnecessary - icing on the cake.He was delighted to have his story published - getting paid for it was the icing on the cake.(UK and ANZ) Icing sugar (US powdered sugar or confectioners' sugar) is soft, powdery sugar used to make icing for cakes.See picture: Preparing food