Definition of "Occupation" :
noun: the act of occupying or taking possession of a building
"Occupation of a building without a certificate of occupancy is illegal."
noun: the principal activity in your life that you do to earn money
noun: any activity that occupies a person's attention
"He missed the bell in his occupation with the computer game."
noun: the control of a country by military forces of a foreign power
noun: the period of time during which a place or position or nation is occupied
"During the German occupation of Paris."