Giant oil reproduced in engraving (8)
I believe the answer is:
intaglio
'engraving' is the definition.
(thesaurus)
'giant oil reproduced' is the wordplay.
'reproduced' indicates an anagram (I've seen 'reproduce' mean this).
'giant'+'oil'='giantoil'
'giantoil' with letters rearranged gives 'INTAGLIO'.
'in' acts as a link.
(Other definitions for intaglio that I've seen before include "Seal with a sunken design" , "Design etched into a surface" , "carved design" , "favoured artist's technique" , "hollowed stone" .)