priority (noun, pl. priorities;nomenclature term) – one major principle of Linnaean nomenclature governing the application of valid names, i. e., the oldest name of a taxon has priority. This is largely a matter of giving credit to the taxonomist, who first described a particular taxon and it is not a necessary requirement for naming conventions. Although much criticized for instability of names, the principle of priority has nevertheless been surprisingly resilient, in part because it guaranteed a generally accepted set of rules for each taxonomist to deduct if a name is valid. The principle of priority nevertheless does not apply universally to all names. In some instances name changes solely for the sake of priority would cause considerable taxonomic upheaval and as a consequence, names that do not date back to the earliest valid publication can be conserved.