Understanding medicine is primarily needed in hepatic transplant (8)
I believe the answer is:
empathic
'understanding' is the definition.
(thesaurus)
'medicine is primarily needed in hepatic transplant' is the wordplay.
'is primarily' says to take the initial letters.
'needed in' means one lot of letters goes inside another.
'transplant' is an anagram indicator.
The first letter of 'medicine' is 'm'.
'hepatic' is an anagram of 'epathic'.
'm' inserted into 'epathic' is 'EMPATHIC'.
(Other definitions for empathic that I've seen before include "showing rapport" , "Sensitive to the experiences of others" , "Understanding others' feelings" , "Emotionally sensitive" , "Feeling" .)