1. (chemical analysis) a counterweight used in chemical analysis
consists of an empty container that counterbalances the weight of the container holding chemicals

2. the weight of a motor vehicle, railroad car, or aircraft without its fuel or cargo

3. weedy annual grass often occurs in grainfields and other cultivated land
seeds sometimes considered poisonous

Synonym: darnelbearded darnelcheatLolium temulentum

4. any of several weedy vetches grown for forage

5. an adjustment made for the weight of the packaging in order to determine the net weight of the goods