Assimilate mentally (6)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
digest
'assimilate mentally' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for digest that I've seen before include "Gradually come to understand" , "Long walk, itinerant person" , "abstract" , "Process food" , "Absorb, in stomach or mind" .)