Printing term to denote accuracy though it appears otherwise (3)
I believe the answer is:
sic
'printing term to denote accuracy though it appears otherwise' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for sic that I've seen before include "Written exactly thus" , "Urge to attack" , "Thus among musicians" , "(Of quoted word) exactly so" , "Like" .)