Farther in, however, the clan names grow rarer; and where we find them they are not hams or tuns, regular communities of Saxon settlers, but they show, by their forestine terminations of hurst, ley, den, and field, that they were mere outlying shelters of hunters or swineherds in the trackless forest. Such are Billinghurst, Warminghurst, Itchingfield, and Ardingley.
Source: wiktionary