While "gelato" is said to be the the Italian word for "ice cream", that's like saying "cricket" is the British word for "baseball". In Italy, gelato is a frozen dessert that is traditionally made with whole milk and without added cream, meaning that the milkfat percentage is around 3.8%. It is also traditionally free of eggs and stabilizers. Traditionally, gelato has very little air whipped into it while freezing, leaving it rather dense, and is not hardened in a blast freezer like ice cream, so it is served semi-frozen near the consistency of soft-serve.
However, because gelato is not a legally defined term here in the Colonies, one most often finds a bastardized version over here. The low milkfat and lack of hardening of traditional gelato makes it unstable and prone to getting icy in a day or two, so it's unsuitable for life on a grocery store shelf. That so-called "gelato" that you bought in the fancy container at your local market is actually low-fat, gummed-up ice cream in a nice Italian suit.