Coffee can put a hotheaded in a coma! (5)
I believe the answer is:
mocha
'coffee' is the definition.
(type of coffee drink)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for mocha that I've seen before include "It may end up as grounds" , "Coffee flavour" , "Kid" , "Strong dark coffee" , "Arabian coffee" .)