any unit used in linear measurement, as the inch, foot, meter, etc. Origin of linear measure. 1885-1890. First recorded in 1885-90.
Realistically, you could put any icing you wanted on a carrot cake. The wonderful beauty of cooking is that you can make it to your liking. But, the traditional icing that most people put on carrot cake is cream cheese icing.
1 Finally stir in the carrot mixture and the walnuts. Pour evenly into the prepared pans.  Bake for 45 to 50 minutes in the preheated oven, until cake tests done with a toothpick. Cool for 10 minutes before removing from pan.