The question from the title sounds ridiculous, but there is a reason for it. Different languages have different names for the staysail, the triangular sail attached to the forestay, with the tack in the bow and trimmed with sheets, one at each side. The English language is usually the official language in terms of what’s what on a sailing yacht but that does not always apply. Again, in different countries different dialects are used for the naval terminology so some terms originate from coastal dialects of the country.
Basically, the jib is basically a triangle-shaped sail placed ahead of the foremast and does not reach aft of the mast. The genoa (or genova) is pretty much the same, but with a slight difference in reach. It is a large foresail that reaches aft past the mast and extends beyond the luff of the mainsail. Mediterranean sailors would use the word genoa for the foresail regardless of its reach. More knowledgeable ones would make a difference with adding some percentage. For example, a 120% genoa would actually be a foresail that reaches around 20% of its foot length beyond the luff of the mainsail. A 100% genoa would then be a foresail that reaches exactly to the luff of the mainsail. It might seem difficult in theory, but it is simple to understand in reality.
If you charter a sailing yacht or sail with an international crew, then take five minutes for a short briefing about the names for the crucial parts of the yacht and make the consensus about terminology. At the end of the day, genoa and genova are the same words just as Genoa and Genova are the names for the same city in Italy. My next quest would be to find a link between the name of the city and the slang name for the sail.
I wish you a calm sea, a fine wind and a strong mast!