Toponymy
According to a widespread theory, that name, which is not unique to this particular commune, is a distortion, in the medieval period, from the Late Latin taxo, ionis, itself of Celtic origin, meaning “the badger”. In Old French, it became Taisson. The first settlements were allegedly built in a place where badgers used to dig their burrows.
But the name Tesson could also very well be a reference to a Gallo-Roman villa belonging to a certain Tessius or Thessius, hence in Latin Tessionem (Tessius estate and Tessianus, a, um as an adjective (applied to villa or fundus) and, alternatively, Tessiacum, with the suffix of Gallic origin acum, also meaning "belonging to".
In fact, in some ancient documents, including the lists of parishes of the archpriest of Pons (diocese of Saintes) contained in two “pouillés” (a “pouillé” being an inventory of ecclesiastical benefices) of 1648 and 1683, the village seems to be called Thessac, which clearly originates from Tessiacum.
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