Many nouns, particularly proper names, in particular, are fully Latinized and declined regularly according to their stem-characteristics.
These variations occur principally in the singular; in the plural the declension is usually regular.
In the accusative singular, many proper and some common nouns, imparisyllabic, often take the Greek -a for -em.
A few Greek nouns in -os, mostly geographical, belong to the second declension, and sometimes have an accusative in -on such as Dēlos, Acc.
Greek neuter nouns in -ma (Gen., -matis) always make their dative and ablative plurals in -īs instead of -ibus.