Nuclear Polynesian refers to those languages comprising the Samoic the Eastern Polynesian branches of the Polynesian group of Austronesian languages.

The Eastern Polynesian languages include Rapa Nui, and the central branch, comprised of Rapan, and the Marquesic and Tahitic languages.

Nuclear Polynesian is differentiated, among Polynesian languages, by its distinguishing characteristics from the Tongic languages spoken in most of Tonga and in Niue.