Isle of the Sea
Everything that is not part of the great Euro-Asian-African land mass. Although North America is currently regarded as a continent, in the Book of Mormon vernacular, it is an isle of the sea (see 2 Nephi 7:5). Further, most of Israel was relocated onto the isles of the sea (see 1 Nephi 7:2). So when the Lord affirms He speaks to those on the isles of the sea, He is confirming that there are multiple locations, involving multiple parties, each one of which has received sacred communication from Him.1
1 “2 Nephi 29:6–7,” Aug. 11, 2010, blog post.