Micronesia (from Greek: μικρός, mikrós, "small" + Greek: νῆσος, nisos, "island") is a subregion of Oceania, comprising thousands of small islands in the western Pacific Ocean. It has a shared cultural history with two other island regions, Polynesia to the east and Melanesia to the south.The region has a tropical marine climate, and is part of the Oceania ecozone.