-ia


-ia
a suffix of nouns, especially having restricted application in various fields, thus, in medicine (disease: malaria), in geography (countries: Romania), in botany (genera: Wisteria), in names of Roman feasts (Lupercalia), in Latin or Latinising plurals (Reptilia, bacteria), and in collectives (insignia, militia).

{Latin or Greek, both from -i-, original or connective vowel + -a (feminine singular nominative ending) or -a (neuter plural nominative ending)

Australian English dictionary. 2014.