Habitational name from Wadden Hall in Waltham, Kent, derived from either the Old English given name Wada or from wæden "made of woad, woaden, bluish" combined with halh "nook, recess".
Possibly derived from Woodhill in Wiltshire, England, derived from Old English wad "woad" and hyll "hill". Alternatively, could be from the Middle English given name Wadel.