Made an identical copy of an organism (6)
I believe the answer is:
cloned
'made an identical copy of an organism' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for cloned that I've seen before include "Propagated like Dolly the sheep" , "Produced a replica of" , "Made an identical copy of a living organism" , "with many copies" , "eg Like Dolly the sheep" .)