Gravity

noun

1. The state or condition of having weight; weight; heaviness.
2. The state or condition of being grave; seriousness.

   "I hope you appreciate the gravity of the situation."

3. The lowness of a note.
4. Force on Earth's surface, of the attraction by the Earth's masses, and the centrifugal pseudo-force caused by the Earth's rotation, resulting from gravitation.
5. (in casual discussion, also) Gravitation, universal force exercised by two bodies onto each other (gravity and gravitation are often used interchangeably).