Under various forms, such as Tunne/a, Tonne or Thonna, we first encounter this surname in the Militia Roster of 1419.
With fish featuring heavily on this coat of arms one could easily assume that this surname originated from the Italian tonno, meaning “tuna". However, it is much more likely that it derives from the Italian surname Tonda, meaning “rotund, circular” and refers to a person that is ‘plump or chubby’.
Fish are far less commonplace in Maltese heraldry than one would think. They are generally used to to suggest a bearer's connection with the sea or fishing.