Bundle returned from the laboratory (4)
I believe the answer is:
bale
'bundle' is the definition.
(bale is a kind of bundle)
'returned from the laboratory' is the wordplay.
'returned' is a reversal indicator.
'from' says the answer is hidden in the clue.
'elab' is hidden in the letters of 'the laboratory'.
'elab' back-to-front is 'BALE'.
(Other definitions for bale that I've seen before include "Evil - bundle" , "Large bundle as of straw" , "Bound bundle" , "Parcel" , "Bundle of goods" .)