gravitational force
      n : (physics) the force of attraction between all masses in the
          universe; especially the attraction of the earth's mass
          for bodies near its surface; "the more remote the body
          the less the gravity"; "the gravitation between two
          bodies is proportional to the product of their masses and
          inversely proportional to the square of the distance
          between them"; "gravitation cannot be held responsible
          for people falling in love"--Albert Einstein [syn: gravity,
           gravitation, gravitational attraction]