The name Penruddock is Cumbric. With both red soil and red sandstone in the area to the south, the word Penruddock is likely derived from the word Pen (hill) and a derivative of the word rhudd (red). Red Hill is also believed to be the translation of the word Penrith and an area called Redhills now lies between the two. The village of Penruddock itself is situated over limestone which is visible in many places, with craggy outcrops and a limestone pavement on the eastern boundary, and the remains of an ancient lime burning kiln on the north western boundary. The soil over the limestone is a fairly heavy clay which retains water, with the result that it helps keep vegetation alive during times of drought, but creates very wet conditions for long periods during the winter months.