Reel showing lead in Garbo embraced by old-timer (7)
I believe the answer is:
stagger
'reel' is the definition.
(I know that reel can be written as stagger)
'lead in garbo embraced by old-timer' is the wordplay.
'lead in' indicates taking the first letters.
'embraced by' is an insertion indicator.
'old timer' becomes 'stager' (I am not sure about this - if you are sure you should believe this answer much more).
The first letter of 'garbo' is 'g'.
'g' inserted into 'stager' is 'STAGGER'.
'showing' is the link.
Can you help me to learn more?
(Other definitions for stagger that I've seen before include "Reel; amaze" , "Walk as if about to fall" , "Surprise" , "Pitch" , "Reel - astound" .)