gravity
n. uncountable C1 Advanced Oxford US //ˈɡɹævəti// UK //ɡɹˈævɪti// grav·i·ty
n. the invisible force that pulls objects toward each other. On Earth, it is what keeps you on the ground and makes things fall when you drop them.
n. the fundamental physical force that attracts objects with mass toward one another. By extension, it also describes the extreme seriousness or alarming importance of a situation.
The Earth's gravity keeps the moon in orbit.
Astronauts experience zero gravity in space, which allows them to float freely inside the station.
Einstein's general theory of relativity revolutionized our understanding of gravity, describing it not merely as a pull but as a curvature of spacetime caused by mass and energy.
Usage
Uncountable in both its scientific sense and when referring to the seriousness of a situation.