preoccupied

Preoccupied means so taken up with one thought that nothing else gets through. Being spoken to and not hearing a word.

It takes with: preoccupied with money, preoccupied with the meeting tomorrow. The word describes a state that is visible from outside, which is why it usually appears as he seemed preoccupied. It differs from distracted, because distraction pulls the mind in many directions and preoccupation holds it in one. The noun is preoccupation, which can also mean the thing itself, as in his great preoccupation was the garden.