Poundage/ˈpaʊndɪdʒ/ Definition 1 of 3Pro Tip 1/3Transportation Costs Poundage can refer to extra costs when you ship items based on weight; heavy items cost more. The parcel's high poundage increased the shipping cost. Pro Tip 2/3Avoid Surprises Be aware of poundage fees to prevent unexpected expenses when mailing or shipping goods. I checked the poundage rates before sending my package. Pro Tip 3/3Weight Terms Poundage is a more specific term for weight-based fees than just calling them 'shipping costs'. The courier's invoice listed a line for poundage.