a promontory of the south coast of England, in the south of Kent, near the town of Lydd. It is a low-lying broad bank of shingle, forming the seaward apex of the great level of the Romney Marshes. Its seaward accretion is estimated at 6 ft. annually. Its formation is characteristic, consisting of a series of ridges forming a succession of curves from a common centre. It is unique, however, among the great promontories of the south coast of England, the accretion of gravel banks falling into deep water contrasting with the cliff-bound headlands of the North Foreland, Beachy Head and the Lizard, and with the low eroded Selsey Bill, off which the sea is shallow. A lighthouse (50 55' N., o 58' E.) stands on the ness, which has been the scene of many shipwrecks, and has been lighted since the time of James I. There are also here Lloyds' signalling station, coast-guard stations, and the terminus of a branch of the SouthEastern & Chatham railway.
The name Dungeness has also been applied elsewhere; thus the point on the north side of the eastern entrance to Magellan Strait is so called, and there is a town of Dungeness near a promontory on the coast of Washington, U.S.A. (Strait of Juan de Fuca).