It is a member of the Micronesian family of Austronesian languages. Its ISO 639 codes are 'na' and 'nau'.
In 1907, Philip Delaporte published his pocket German-Nauruan dictionary (Taschenwörterbuch Deutsch-Nauruisch). The dictionary is small (10.5 x 14 cm), with 65 pages devoted to the glossary and an additional dozen to phrases, arranged alphabetically by the German. Approximately 1650 German words are glossed in Nauruan, often by phrases or synonymous forms. There are some 1300 'unique' Nauruan forms in the glosses, including all those occuring in phrases, and ignoring diacritical marks.Delaporte's Nauruan Dictionary