IPA: /ˌɑːrkɪˈpɛɪɡloʊ/
KK: /ˌɑr.kɪˈpeɪ.ɡloʊ/
A large group of islands or a sea that contains many scattered islands.
The Philippine archipelago is known for its beautiful beaches and diverse wildlife.
Archipelago → It is formed from "archi-" (from Greek "archi", meaning chief or principal) and "pelagos" (from Greek "pelagos", meaning sea). The word refers to a group of islands in the sea, with the implication of being a principal or significant collection of landforms in a marine environment.
Think of 'chief' ('archi-') islands in the 'sea' ('pelagos') — that's why an archipelago is a significant group of islands in the ocean.
No commonly confused words.