Emily Dickinson Lexicon

ARCH-I-PEL'A-GO, n. [Authors are not agreed as to the origin of this word. Some suppose it to be compounded of αρχος, chief, and πελαγος, sea; others, of Αιγαιος, and πελαγος, the Egean sea. See Gibbon, Mitford, and Ed. Encyc.]

In a general sense, a sea interspersed with many isles; but particularly the sea which separates Europe from Asia, otherwise called the Egean sea. It contains the Grecian isles, called Cyclades and Sporades.