In biological taxonomy, a combinatio nova refers to the formal renaming of an organism's scientific name when it is transferred to a different genus, reclassified within a different species, or its taxonomic rank is altered. Unlike the naming of a new species, a combinatio nova does not describe a previously unknown organism but reorganizes an existing name to reflect updated understanding of its relationships or classification. For example, when a species is moved to a new genus, its specific epithet is retained and combined with the new genus name, forming the new combination. This process ensures consistency and accuracy in naming while adhering to the rules established by nomenclature codes.