Recorded in several forms including Tregenna, Tregonna, Tregunna and even Tregunia, this is a Cornish surname. It is locational from any of the various places or even individual dwellings called Tregenna or Tregunna, which apparently translate as 'The house on the down'. In windswpt Cornwall the opportunity for such a naming was considerable, and therefore not surprisingly the resulting surname is widely recorded throughout the county. It does however share a common characteristic with most Cornish names. It is rarely found outside the county. In general, locational surnames as given to people in most European countries, applied after they left their original homes to move somewhere else. Not so in Cornwall where people were called by the name of the place where they lived. People who left Cornwall were usually called Cornish or Cornwall, having presumably 'lost' their original names. In this case early examples of the surname recordings taken from surviving church registers of the county of Cornwall include: William Tregonna at St Erth, on June 1st 1563, and later that of another William, this time Tregunna, at Veryan, on March 22nd 1801.