Be told (4)
'be told' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for hear that I've seen before include "attend" , "Hark" , "Perceive aurally" , "Be informed of" , "Discover aurally" .)
(Other definitions for truth that I've seen before include "real story" , "Actuality" , "Honesty" , "Verified fact" , "known facts" .)