Possible Clues:

• Counterweight
• Weedy annual grass, often occurs in grainfields
• Vehicle's empty weight
• Deduction from gross
• Counterbalance
• Allowance for package weight; vetch
• Weight of a container on a scale
• Perhaps 'tis, and 'tis a weighty matter
• Tis and tis, perhaps, a matter of weight
• Audibly rip old weed