It is well known that many of the major island-names of the archipelago consisting politically of Ireland, the United Kingdom and Crown dependencies are etymologically obscure. In this paper, I present and analyse a corpus of those which remain unexplained or uncertainly explained, for instance 'Man' and 'Ynys Môn', 'Ar(r)an', 'Uist', 'Seil', 'Islay', 'Mull', 'Scilly', 'Thanet', 'Sark', among others. It is timely to do this, since in the disciplines of archaeology and genetics there is an emerging consensus that after the last Ice Age the islands were repopulated mainly by people from a refuge on the Iberian peninsula. This opinion is at least superficially compatible with Theo Vennemann’s Semitic and Vasconic hypotheses, i.e., that l...