 Another explanation (and the one most favoured today) is based on the greater shrinkage of peat, compared to that of silt.This theory suggests that the surrounding peat lands have subsided more than the silt-filled banks of the roddon, leaving the banks raised above the general level of the area.The term "roddon" may be a corruption of the now rare "rodham", which meant "near a river where osiers grow", with particular reference to the River Thames; an osier is a willow used in basket-making.