Indistinguishable (4)
'indistinguishable' is the definition.
(I know that indistinguishable can be written as identical)
This is the entire clue.
(Other definitions for identical that I've seen before include "Exactly alike, the same in every detail" , "Selfsame" , "showing no change" , "Aid client to be the very same" , "Indistinguishable" .)
'indistinguishable' is the definition.
(similar in meaning)
This is all the clue.
(Other definitions for same that I've seen before include "Identical, not different" , "Equal in amount or value" , "Identical or similar" , "Aforesaid" , "Ditto" .)