Heard worker's insult as deception (7,2,4)
I believe the answer is:
sleight of hand
'deception' is the definition.
(sleight of hand is a kind of deception)
'heard worker's insult' is the wordplay.
I cannot really understand how this works, but
'worker' could be 'hand' (hand is a kind of worker) and 'hand' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'as' is the link.
Can you help me to learn more?
(Other definitions for sleight of hand that I've seen before include "Doctor or student doctor" , "Skilful deception" , "Prestidigitation" , "Trickery" , "Legerdemain" .)