All 4 Uses

preoccupied
in
Black Like Me
(Auto-generated)

My greatest preoccupation was that moment of transition when I would "pass over."†
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I was sleepy, I was preoccupied with the magnificent music and I was trying to read while P. D. talked—a long, immensely funny monologue, punctuated every five minutes by: "Well, I'll shut up now and let you concentrate on that.†

preoccupied = took up the attention of
He went through the motions of courteous research, but he could not hide his real preoccupation.†
To live in a world where men do not love, where they cheat and are callous, is to sink into a preoccupation with death, and to see the futility of anything except virtue.†

Definitions:

(1) (preoccupied)
busy thinking about or doing something so that other things are not noticed or done
(2) (meaning too rare to warrant focus)
Much more rarely, preoccupied can mean that someone has already inhabited or taken something.