They aren't pants, but they are really cute with the right outfit, and they are easy to buy to make your butt look fantastic. I mean I prefer jeans but I know people who only ever wear leggings, so I would say they aren't pants, but I won't judge if you wear them as pants. If you buy thick ones, they are just like yoga pants that don't flare at the bottom! Those ones from tna that are see through and people wear them to yoga class are NOT pants, and shouldn't be worn to yoga class. Seriously I really don't want to see that.
Leggings are trousers/pants, but tights are definitely not pants (leggings are not the same as tights). Definitions of leggings: 1. "Tight-fitting stretch trousers, typically worn by women or girls"; 2. "Close-fitting knit pants"; 3. "Very tight trousers made from a material that stretches easily, usually worn by women"; 4. "Trousers worn by women and girls that stretch and fit very closely to their legs"; 5. "Close-fitting trousers worn by women and children".