grav·i·ty
–noun, plural -ties.
1. the force of attraction by which terrestrial bodies tend to fall toward the center of the earth.
2. heaviness or weight.
3. gravitation in general.
4. acceleration of gravity.
5. a unit of acceleration equal to the acceleration of gravity. Symbol: g
6. serious or critical nature: He seemed to ignore the gravity of his illness.
7. serious or dignified behavior; dignity; solemnity: to preserve one's gravity.
8. lowness in pitch, as of sounds.