Latin, appendicium, membrum.
A dependency, or member, was a holding dependent upon a manor. Domesday Book describes large numbers of outliers and jurisdictions which belonged in some sense to a central manor. The exact status of many dependencies in Domesday Book, however, was not always recorded. The majority of these unidentified dependencies were probably outliers. Dependencies and members occur disproportionately in circuits 2, 4 and 5.
For more detail on the unnamed, and often unmentioned, dependencies of manors, see H.C. Darby, Domesday England (1977).