Spiked (5)
I believe the answer is:
'spiked' is the definition.
('lace' can be a synonym of 'spike')
This is the entire clue.
(Other definitions for laced that I've seen before include "Spiked drink - thrashed" , "Intertwined" , "Added alcohol to (drink)" , "with extra spirit" , "Oxford will always be" .)