Doctor is calm about uranium? Pleasing to hear (7)
I believe the answer is:
musical
'pleasing to hear' is the definition.
'doctor is calm about uranium?' is the wordplay.
'doctor' indicates anagramming the letters.
'about' indicates putting letters inside.
'uranium?' becomes 'u' (U is the chemical symbol for uranium).
'is'+'calm'='iscalm'
'iscalm' is an anagram of 'msical'.
'msical' enclosing 'u' is 'MUSICAL'.
(Other definitions for musical that I've seen before include "Pleasant-sounding" , "Stage entertainment" , "Eg, Les Miserables" , "Cats perhaps" , "eg Chicago" .)