This article analyses the functions and meanings of the reflexes of the Proto-Oceanic (POc) prefix *paRi- in New Caledonian languages and, based on comparisons with other Austronesian languages, seeks to account for their broad polyfunctionality and polysemy in New Caledonia. POc *paRi- originates from Proto-Austronesian and Proto-Malayo-Polynesian *paR-, as evidenced by their reflexes in various Formosan and Malayo-Polynesian languages. In Formosan languages, these prefixes are reciprocal markers and their combination with root reduplication marks plurality of reciprocal participants. In Malayo-Polynesian languages, the prefixes have a greater variety of functions and meanings: they are basically intransitive actor focus morphemes which also express middle voice and reciprocity, as well as plural relationship, intensive, and frequentative meanings (in this latter case, they may combine with reduplicated roots). In Oceanic languages, the reflexes of POc *paRi- express symmetrical, plural relationship, and lower transitivity. POc *paRi- could also combine with two suffixes (POc * i, * aki) or with reduplication to express some other meanings (intensive, iterative, distributive, dispersive), as attested in various Oceanic languages. Thus, originally reciprocal prefixes in Formosan languages evolved into more polysemous morphemes in Malayo-Polynesian languages and developped in more or less conservative or innovative ways in Oceanic languages. In the northern New Caledonian languages, the decay of some of their combined suffixes and of reduplication probably triggered the conflation of these various functions and meanings onto the preserved and productive prefixes.