Subtle humour fey perhaps? (5)
I believe the answer is:
irony
'subtle humour' is the definition.
(I've seen this before)
'fey perhaps?' is the wordplay.
I cannot quite see how this works, but
'perhaps?' could be 'y' (I've seen this in other clues) and 'y' is found in the answer.
The remaining letters 'iron' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for irony that I've seen before include "Use of words to convey the opposite of what they normally mean" , "(Words) inferring the opposite of what's actually said" , "Use of words to imply the opposite of what they mean" , "Socratic method of discussion" , "form of sarcasm" .)