Gravity: The force of attraction between the earth and any other body is called gravity. It is the force that attracts a body toward the center of the earth, or toward any other physical body having mass.
Law of gravitation: Any two particles in the universe attract each other with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. This force acts along the line joining the two particles.
Gravitation: The force of attraction between two objects or particles in the universe is called gravitation. It is a force manifested by acceleration toward each other of two free material particles or bodies or of radiant-energy quanta.
Gravitational field: The spar around which gravitational is effective is called gravitational field.