Immersed or engrossed (7)
I believe the answer is:
steeped
I believe this is a double definition.
'immersed' is the first definition.
('steep' can be a synonym of 'immerse')
'engrossed' is the second definition.
('steep' can be a synonym of 'engross')
(Other definitions for steeped that I've seen before include "Soaked in liquid" , "Soaked in water" , "Saturated or let sit in a liquid" , "wet" .)