darby
n. countablen. a long, flat tool with two handles that builders use to make wet concrete or plaster smooth. It helps level large areas quickly.
n. a long, straight-edged tool, typically made of wood or metal and featuring two handles, used for levelling and smoothing large surfaces of wet plaster or concrete.
The worker used a darby to level the fresh concrete.
After pouring the slab, the mason carefully worked the darby across the surface to remove any high spots before the concrete set.
While a small trowel is sufficient for detail work, a darby is essential for achieving a uniform plane across expansive sections of wall plaster or floor screed.
Commonly used in the construction and masonry trades; the term is more frequent in British English than American English.