Preoccupied (8)
'preoccupied' is the definition.
(obsessing is a kind of preoccupying)
This is the entire clue.
(Other definitions for obsessed that I've seen before include "Excessively preoccupied" , "Compulsively concerned with something" , "Fanatical" , "With compulsion" , "Showing excessive or compulsive concern with something" .)
'preoccupied' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for abstracted that I've seen before include "Removed - preoccupied - absent-minded" , "miles away" , "not paying attention" , "Summarised -- lacking concentration" , "without concentrating" .)