Of or pertaining to an archipelago; of the nature of an archipelago.(adjective)
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Use "archipelagic" in a sentence
"In 1928, Indonesia declared Bahasa Indonesia the national language, the language of unity for everyone in this archipelagic country."
"As an archipelagic state, Indonesia is understandably wary of China becoming the preponderant maritime power in the Asia Pacific."
"Maritime Claims (measured from claimed archipelagic baselines): Territorial sea to 12 nautical miles and an exclusive economic zone to 200 nautical miles."