Son concealing longing to be a theatre performer? (7)
I believe the answer is:
surgeon
'a theatre performer?' is the definition.
'surgeon' can be an answer for 'performer?' (I have seen 'Performer of operations ' mean 'surgeon' so perhaps 'performer' could also mean 'surgeon'). I am not sure about the 'a theatre' bit.
'son concealing longing' is the wordplay.
'concealing' means one lot of letters goes inside another.
'longing' becomes 'urge' (both can mean a desire).
'son' going around 'urge' is 'SURGEON'.
'to be' is the link.
Can you help me to learn more?
(Other definitions for surgeon that I've seen before include "Doctor in the navy" , "One operating in theatre" , "incisive person" , "Operating medical practitioner" , "Sawbones" .)