'dumper' definitions:

Definition of 'dumper'

From: WordNet
noun
Truck whose contents can be emptied without handling; the front end of the platform can be pneumatically raised so that the load is discharged by gravity [syn: dump truck, dumper, tipper truck, tipper lorry, tip truck, tipper]

Definition of 'dumper'

From: GCIDE
  • dumper \dumper\ n. same as dump truck.
  • Syn: dump truck. [WordNet 1.5]