third island chain

Etymology
By extension, from second island chain

Proper noun

 * 1)  The Andaman Islands, Nicobar Islands, Sumatra; from Burma in the north to either the Indonesian Archipelago, or Australia in the south.
 * 2)  The Aleutian Islands, Emperor Seamounts, Hawaiian Islands, Line Islands, New Zealand; from Alaska to New Zealand or Tasmania and Australia.

Usage notes
Geopolitical terminology, regarding the presumed geopolitical control zone aspired to by a rising People's Republic of China.

Related terms

 * / First Island Chain
 * / Second Island Chain