Mac gives Joe a hiding and that's charming! (5)
I believe the answer is:
magic
'charming' is the definition.
(thesaurus)
'mac gives joe a hiding' is the wordplay.
'gives joe' becomes 'gi' (I can't justify this - if you can you should give a lot more credence to this answer).
'a hiding' is an insertion indicator.
'mac' going around 'gi' is 'MAGIC'.
'and that's' acts as a link.
Can you help me to learn more?
(Other definitions for magic that I've seen before include "Unexpectedly produce" , "Spelling?" , "Fungus causing trips?" , "Enchantment" , "Prestidigitation" .)