preoccupied

Synonyms: absent absent-minded absorbed abstracted airheaded asleep bemused bugged daydreaming deep distracted distrait engaged engrossed faraway fascinated forgetful have on the brain heedless hung up immersed inconscient intent lost lost in thought mooning moony oblivious obsessed rapt removed spellbound spread out taken up unaware woolgathering wrapped-up

Antonyms: observant thoughtful unoccupied