Secret split into specific parts (10)
I believe the answer is:
classified
'secret' is the definition.
(similar in meaning)
'split into specific parts' is the wordplay.
I cannot really understand how this works, but
'parts' could be 'las' (la is a kind of part) and 'las' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for classified that I've seen before include "Categorised; secret" , "Ordered" , "Arranged in categories" , "to be kept secret" .)