Sycophant's aspirate misplaced (8)
I believe the answer is:
parasite
'sycophant's' is the definition.
(I've seen this in another clue)
'aspirate misplaced' is the wordplay.
'misplaced' indicates anagramming the letters (letters in the wrong places).
'aspirate' anagrammed gives 'PARASITE'.
(Other definitions for parasite that I've seen before include "unwanted guest" , "Organism growing on or in another" , "Relies on host to survive" , "Self-interested hanger-on" , "Organism that lives on another" .)