For amusing company, Mickey has no answer (5)
I believe the answer is:
comic
'for amusing' is the definition.
(thesaurus)
'company mickey has no answer' is the wordplay.
I cannot quite see how this works, but
'company' could be 'co' (abbreviation) and 'co' is found within the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for comic that I've seen before include "Priceless" , "Funny, droll" , "Wag" , "Child's magazine" , "Garden perhaps" .)