Dodgy two shakes, first one ignored (4)
I believe the answer is:
iffy
'dodgy' is the definition.
(both can mean dubious)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for iffy that I've seen before include "Not certain, doubtful" , "Problematic" , "Questionable - uncertain" , "Doubtful, not definite" , "not kosher" .)