archipelagon.

Etymology: < Italian arcipelago, < arci- chief, principal (arch- prefix 4) + pélago deep, abyss, gulf, pool; cognate with Spanish piélago , Portuguese pego , Provençal peleg < Latin pelagus (very common in medieval Latin), < Greek πέλαγος sea. In most of the languages the word had at first the prefix in the native form: Old Spanish arcipielago , Old Portuguese arcepelago , Middle English archpelago , arch-sea . All except Italian have now archi- . Compare also arches n.No such word occurs in ancient or mediæval Greek; Ἀρχιπέλαγος in modern Greek dictionaries is introduced from western languages. Arcipelago occurs in a Treaty of 30th June 1268, between the Venetians and the emperor Michael Palaeologus: ‘Item, quod pertinet ad insulas de Arcipelago’; it is used also by Villani c1345. It was evidently a true Italian compound like arciduca, arcipoltrone, arcifelice, suggested probably by the medieval Latin name of the Ægean Sea, Egeopelagus (Venetian state-papers of 1419 have still Ducatus Egeopelagi), representing Greek αἰγαιοπέλαγος, αἰγαῖον πέλαγος, and alluding to the vast difference in size between this and the lagoons, pools, or ponds, to which pelago was popularly applied. That it was a corruption or perversion of Egeopelago itself is less probable.