Quarantine giving empty sample, say, in jar (9)
I believe the answer is:
segregate
'quarantine' is the definition.
(thesaurus)
'empty sample say in jar' is the wordplay.
'empty' means to remove the middle letters.
'say' becomes 'eg'.
'in' means one lot of letters goes inside another.
'jar' becomes 'grate' (make unpleasant sound).
'sample' with its centre removed is 'se'.
'eg' put inside 'grate' is 'gregate'.
'se'+'gregate'='SEGREGATE'
'giving' acts as a link.
(Other definitions for segregate that I've seen before include "Cut off" , "put to one side" , "set apart from others" , "Quarantine with easter egg" , "Keep apart" .)