grav·i·ty   (grv-t) n. Physics. The natural force of attraction exerted by a celestial body, such as Earth, upon objects at or near its surface, tending to draw them toward the center of the body. The natural force of attraction between any two massive bodies, which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. Gravitation. Grave consequence; seriousness or importance: They are still quite unaware of the gravity of their problems. Solemnity or dignity of manner.