preoccupied   adjective
 She's been very preoccupied (=giving her attention to esp. one thing) recently because
 her mother has been very ill.
 He is so preoccupied with his own problems that he has been incapable of working in
 the last few weeks.
 Why does the media seem to have become so preoccupied with personal morality and
 family organization?
 Preoccupied doctors hurried towards the hospital entrance.

 preoccupation   noun
 My main preoccupation (=The thing that I am thinking about most) now is trying to keep
 life normal for the sake of my two boys. [C]
 The opening chapter of the book introduces the school staff and their problems and
 preoccupations, both emotional and academic. [C]
 Lately, his preoccupation with (=thinking only about) football had caused his marks at
 school to slip. [U]
 Such preoccupation with (=thinking only about) your work isn't healthy. [U]