Attested:  Probably used by Pytheas in about 325 BC (whose work survives only in quotation by later authors) when it was spelled with an initial P, as Πρεττανια (Prettania) or similar.  This was repeated by many later authors (listed here, or by R&S pp 39-40), but the initial letter shifted to B, so that the Latin spelling settled down to Britannia.

Where:  the British Isles

Name origin:  A two-part compound that meant ‘sticking out’, with first part from PIE *per- ‘beyond’, which led to Latin prae ‘before, in front’ etc, and second part from PIE *ten- ‘to extend’, with the vowel A seen in Greek τανυω ‘to stretch out’ and in Tanatis Thanet.  The closest parallel to recorded forms such as Πρεττανια is Πρυτανεια, which meant the office (and duration) of presidency of the deliberative council (βουλη) in cities of ancient Greece, a word that would have been very familiar to men like Pytheas.  It is hard to imagine that visitors saw ancient Britons being especially democratic at their moots, but a president is someone who stands in front of the council, and Britain is an island that stands in front of the Continent.  The modern word pretend has acquired a pejorative sense of falseness, but its original meaning in English was “to stretch, extend, or hold (something) before”, from Latin praetendo.
  It is remarkable that the classic Celtic explanation, based on a precursor of Welsh pryd ‘appearance, form, shape, countenance’, cognate with Irish cruth, is still repeated unchallenged.  Those words suggested as parallels (derived from PIE *kwer- ‘to make’) were first attested more than a thousand years late.  And it is feeble to rely on plurals to explain the -tan- part of the name.

Notes:  Celtic languages systematically fail to explain island names, most noticeably around the Irish Sea.  Many northern barbarians had tattoos (e.g. Ötzi the Iceman had 61), but on ancient Britons they seem to have impressed Caesar enough to comment on their blueness (in his famous remark about vitrum, which is regularly mistranslated as ‘woad’) and it is hard to see how the subset of Britons (whom Tacitus explicitly described as quite diverse in physical appearance) encountered by early travellers differed enough from their Continental neighbours to give a name to the entire island.  Similarly hard to sustain is the delightful idea that ancient Britons were ‘plankies’, named from a word ancestral to German Brett ‘board’ applied to vessels like the Dover Boat.

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Last edited: 20 August 2018