The term 'thoroughly absorbed' can be summarized by two crossword solutions: 'ENTRANCED' (9 letters) and 'RAPT' (4 letters). Both words refer to a state of being deeply engrossed in something, usually an activity or experience. ENTRANCED is a more intense version of RAPT, as it implies a greater level of absorption. Both words suggest that the person is so focused on the activity or experience that they are unaware of their surroundings.