A person, usually a woman, who reads something factual and then tells other people about it in a condescending, or haughty, manner, pretending as if it was common knowledge. The phenomenon can be readily overheard zoos, where there are lots of moms, and lots of factual information.
Person 1: Wow, it's amazing how these wolves don't get cold on the snowy ground.
Zoo mom: They stay warm because they have a special system of veins and arteries in their legs that recirculates their body heat, instead of losing it to the ground.
Person 1: Oh, yes, I see that that is exact what that sign you just read says.