This question has been done over many years of history. It has been tried to find the full meaning from many perspectives such as the social, the philosophical, the etymological . I am going to explain the meaning from the different points of view.

Firstly, the The etymological origin of happiness comes from the latin word "felicĭtas, -ātis" which means prosperity, good luck, fertility."felicĭtas, -ātis" meaning comes from the Romans who had already put his name and surname to this feeling.

Secondly, social point of view, the society explains "happiness" as a very pleasant feeling or a common goal for the people, we have to find it  for to be sucess in our lives. It`s hard to find it and if you   didn`t even find the happiness, you can experience frustration, a feeling that is quite contrary to "your goal in life"

Happy

 

Frustration

  

Thirdly According to the ancient philosophy view, philosophers such as Plato and Socrates. Socrates understood "felicĭtas, -ātis as a purpose of human existence. Althought he explained that could not be achieved at any price. Socrates said "The wisdom and knowledge will guide us on the right path to achieve it". According to Plato  the needed to be happy was to have the balance of the three types of soul; the soul concupiscible, irascible soul and the  rational soul. "To achieve this balance, it required the harmony and is in turn controlled by reason" said

                                                  Socrates                                             Plato 

In my opinion the happiness cannot be understood by a group of people, by a society, a nation, or the universe. It is more something for each one, each one understands his or her own happiness. Although you can`t achieve it only, we need to help us all together.

 

Be happy