Psychic pitman conveys alarm (4,6)
I believe the answer is:
mind reader
'psychic' is the definition.
(someone with psychic powers)
'pitman conveys alarm' is the wordplay.
I cannot quite understand how this works, but
'alarm' could be 'dread' (I've seen this before) and 'dread' is found in the answer.
'pitman' could be 'miner' (I've seen this before) and 'miner' is present in the leftover letters.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for mind reader that I've seen before include "Man with intuition" , "one knows what he is thinking" , "Thought interpreter" , "I know what you're thinking!" , "Psychic" .)