Like American leaving orient, in summary (6)
I believe the answer is:
digest
'summary' is the definition.
(I've seen this in another clue)
'like american leaving orient' is the wordplay.
'like' becomes 'dig' (to dig can mean to appreciate or 'get').
'american' becomes 'a' (common abbreviation - e.g. in organisation names).
'leaving' suggests deleting specific letters.
'orient' becomes 'east' (synonyms).
'east' with 'a' removed is 'est'.
'dig'+'est'='DIGEST'
'in' is the link.
(Other definitions for digest that I've seen before include "Take in (information or food)" , "Break down in the stomach" , "Assimilate - summary" , "Absorb, in stomach or mind" , "Synopsis" .)