Variations of the Welsh form are ap Rhiddid, meaning "son of Rhiddid", or even ap Redith, which means "son of Redith", a short form of Meredith.
It is also possible that Priddy was derived from the personal name Predyr or Peredur (perhaps from Old Welsh peri ‘spears’ + dur ‘hard’, ‘steel’), which was borne, in Arthurian legend, by one of the knights of the Round Table.
The name may have been derived from occupational trade, from the Welsh prydydd, meaning "bard".
The name also may have come from those who simply lived in Priddy in Somerset, derived probably from the Celtic words meaning "earth house".
In the case of British Columbia, Canada, politician Penny Priddy, the surname is a respelling of the original "Pretty".