retarder

Definitions

Cars & Driving

  • noun an additive to decrease the evaporation rate of a thinner or reducer in paint; used to improve viscosity in hot weather
  • noun an auxiliary brake used on commercial vehicles and coaches (it is a requirement in some EU countries)

Construction

  • An admixture that delays the setting of cement paste, and hence of mixtures such as mortar- or concrete- containing cement.
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