Oceania is a separate landmass, but it is separated from Asia by very shallow water.
A division of Oceania in the western Pacific Ocean comprising the islands east of the Philippines and north of the equator. It includes the Caroline, Marshall, Mariana, and Gilbert islands.
Is Australia part of Oceania?
a large group of islands in the south Pacific including Melanesia and Micronesia and Polynesia (and sometimes Australasia and the Malay Archipelago)