Cunnit is Dames of course, I did some etymology notes few years back, and of course with Dames we have female goddesses and sheela na gig... so quoting myself......
"Dames has of course taken the word back to Cunnit/or cunnt - an orifice; depicted in Christian faith as the 'mouth of hell', and indeed there is a depiction on the Winterbourne Monkton church font of a 'sheela-na-gig, a grotesque form to frighten medieval worshippers."

"Kennet -Cynetan 939, Chenete 1086, is the name for the East and West Kennet. The Kennet river of course comes from the celtic."

though it must not be forgotten that the town of Mildenhall by the Kennet was called Cunetio by the romans, so perhaps taken from the Iron Age.