Female carrying drug hidden by inmates -- clots! (8)
I believe the answer is:
congeals
'clots' is the definition.
'female carrying drug hidden by inmates' is the wordplay.
'female' becomes 'gal' (gal is a kind of female**).
'carrying' indicates putting letters inside.
'drug' becomes 'e' (e is another name for ecstasy).
'hidden by' is an insertion indicator.
'inmates' becomes 'cons' (con is short for convict).
'gal' placed around 'e' is 'geal'.
'geal' put within 'cons' is 'CONGEALS'.
(Other definitions for congeals that I've seen before include "Coagulates" , "Becomes gelatinous" .)