AsBrittānia from the 1st centuryBCE, fromAncient GreekΒρεττανία(Brettanía), used byDiodorus, earlierνῆσος(nêsos)Πρεττανική(Prettanikḗ) orΒρεττανίαι(Brettaníai), used byPytheas (4th centuryBCE) of the entire archipelago now known as theBritish Isles.
The Ancient Greek name is ultimately from aCeltic ethnonym, reconstructed as earlyBrythonic*Pritani, perhaps from aProto-Celtic*Kʷritanī,*Kʷritenī, whenceWelshPrydyn(“Picts”),Old IrishCruthne,Cru(i)then-túath(“Picts”), fromProto-Indo-European*kʷer-(“to do”).
Brittō m (genitiveBrittōnis);third declension
Third-declension noun.
| singular | plural | |
|---|---|---|
| nominative | Brittō | Brittōnēs |
| genitive | Brittōnis | Brittōnum |
| dative | Brittōnī | Brittōnibus |
| accusative | Brittōnem | Brittōnēs |
| ablative | Brittōne | Brittōnibus |
| vocative | Brittō | Brittōnēs |
BecauseBrittany(“Little Britain”) was settled at the end of the Roman era by migrants from Britain, the original descendants ofBrittō often have the meaning "an inhabitant of Brittany", with a later reborrowing from Classical Latin being used to form the word for "an inhabitant of Great Britain".