In biological classification, circumscriptional names (Latin: nomina circumscribentia) are taxon names that are defined by their circumscription; i.e. the diagnostic feature of the particular set of members included.
Non-typified names other than those of genus or species rank constitute the majority of generally accepted names of taxa higher than superfamily.
The standard nomenclature codes regulate names of taxa up to family rank (i.e. superfamily).
There are no generally accepted rules for the naming of higher taxa (orders, classes, phyla, etc.).
A number of established practices exist as to the use of typified names of higher taxa, depending on group of organisms.