Surprising words: il Dio, il dio
Welcome to the newest category on Parola del Giorno called Surprising Words. These posts will highlight words that do not play by the rules in some way, shape, or form — they have unusual plurals, no plural at all, change gender, and so forth.
The inaugural post is the noun il dio (or Dio), which means god (or God).
When used in its capitalized form (Dio), it refers to the supreme God of whatever religion one to which one is referring.
When one talks about polytheistic religions, such as the ancient Greeks or Romans (which feature prominently in Greek and Italian culture), we do not tend to capitalize it.
When we are talking about gods of a pantheon, note that the plural of il dio is gli dei.
If one is referring just to the female gods of a pantheon, use the noun la dea (plural: le dee).
If you want to learn more about Roman mythology, check out this site.
Wikipedia Italia also has a good listing of the names of Roman mythological gods, goddesses, and heroes.