From the latin gravĭtas, gravity is a physical force the Earth exerts on all bodies in their centre. It is also the force of attraction of the body due to their mass.
The severity is associated with weight, which is the force of gravity exerted by the mass of the planet on all objects that are within its field of gravity. The same body weight may vary from one planet to another, depending on if the mass of the planet in question is different from the mass of the Earth.
This is the physicist, mathematician, philosopher and English inventor Sir Isaac Newton, who is at the origin of the law of universal gravitation (or theory of gravity). According to Newton, anything with mass exerts a gravitational pull on any other object with mass, in addition to the distance between both. The force of attraction is greater that the mass is high; Furthermore, the force of attraction is stronger that the objects are close to one another.
On the other hand, the notion of gravity may apply caution. For example: 'Solemn, the Government spokesman announced with severity the death of the Prime Minister', 'I do not like the scenes where people act with seriousness and without spontaneity.
The term also has to do with the size, the importance or the enormity of the subject: "the seriousness of the epidemic was clearly visible with the death of 20 people in the metropolitan area of the city", "the police officer was injured with gravity due to the four shots of bullet to the body he has suffered.