a gram is how much
Confidence votes 330. A gram is defined as one thousandth of a kilogram (which is defined as the mass of a metal reference weight that is stored in Paris.) One gram is about what one cubic centimeter (one milliliter) of water weighs. A US nickel weighs exactly 5 grams. There are 28.3 grams in an ounce, and 453.6 in a pound. Sometimes stuff that is measured in volume in the US is measured in grams in the metric system. For example, a tablespoon of butter (1/8 a stick) is about 15 grams.