Awaiting or missing cough medicine (9)
I believe the answer is:
expectant
'awaiting' is the definition.
(thesaurus)
'or missing cough medicine' is the wordplay.
'missing' suggests deleting specific letters.
'cough medicine' becomes 'expectorant' (I've seen this before).
'expectorant' with 'or' taken out is 'EXPECTANT'.
(Other definitions for expectant that I've seen before include "Hopeful" , "Pregnant" , "in the club" , "Agog" , "Waiting for something" .)