Suggestion of devilish intention (4)
I believe the answer is:
hint
'suggestion' is the definition.
(I know that suggestion can be written as hint)
'of devilish intention' is the wordplay.
'of' says the answer is hidden in the clue.
'HINT' is hidden in the letters of 'devilish intention'.
(Other definitions for hint that I've seen before include "signal" , "Indicate indirectly" , "Clue - soupcon" , "Helpful suggestion" , "Small trace; clue" .)