Terrible fraud led astray (8)
I believe the answer is:
dreadful
'terrible' is the definition.
(I know that terrible can be written as dreadful)
'fraud led astray' is the wordplay.
'astray' indicates anagramming the letters.
'fraud'+'led'='fraudled'
'fraudled' is an anagram of 'DREADFUL'.
(Other definitions for dreadful that I've seen before include "Dire, alarming" , "Appalling, awful" , "Shockingly bad" , "Informally very bad, perhaps the weather" , "Extremely bad or disagreeable" .)