While searching in my old coin boxes, I found this denarius of Emperor Alexander Severus. The reverse shows Jupiter and legend starting with IOVI. So I thought it's likely to be followed by Conservatori or Vltori etc.. But I was intrigued by the letter N before the letter A. And finally I found a clue. The legend reads IOVI Propugnatori. Something new to me, and willing to know what does this term represent in Latin language or Roman History ?
Forum Ancient Coins' "Numiswiki" is a good place to look when you seek the definition of a numismatic word. http://www.forumancientcoins.com/numiswiki/view.asp?key=IVPITER PROPVGNATOR Apparently "PROPVGNATOR" means Defender. Another definition specific to these coins of Severus Alexander: http://www.forumancientcoins.com/NumisWiki/view.asp?key=IOVI PROPVGNATORI I was unfamiliar with the legend and took a moment to see its use. It doesn't appear to be a common reverse type. Although the search wasn't thorough, I only found it used on coins of Septimius Severus, Severus Alexander, and Postumus.
Another good place to learn about various reverse inscriptions is this page from the old Barry & Darling site.
The reverse inscription means “of Jove Puropugnator”. Both the noun (Jovus) and adjective (propugnator) take the singular masculine genitive ending -i (genitive is translated as “of something”) . The adjective takes the same ending because it agrees with the noun in gender, number, and case. In this case, the noun is masculine, singular, and genitive. Also, propugnator appears related to the verb pugnare, that is, to fight. Got it? I haven’t really ever tried to explain Latin grammar to anyone until now, so let me know if some stuff is confusing.
I had a Gordian Ant with MARTEM PROPVGNATOREM on the reverse, apparently struck during his Persian campaign. Like this one:
