"Ordinary matter" refers to the physical substance that makes up the things we see and interact with in everyday life. It includes everything that is composed of atoms, such as objects, living beings, and even the air we breathe. Full definition
Their results suggest that current estimates of the amount of ordinary matter in the universe may be too high. (sciencemag.org)
Dark matter makes up 80 per cent of the stuff in the universe, but it is difficult to see because it barely interacts with ordinary matter except through gravity. (newscientist.com)
In contrast, ordinary matter makes up only about 15 percent of the mass of the universe. (sciencenewsforstudents.org)