Sot staggering in upright stance (7)
I believe the answer is:
posture
'stance' is the definition.
(I've seen this before)
'sot staggering in upright' is the wordplay.
'staggering' indicates anagramming the letters.
'in' indicates putting letters inside.
'upright' becomes 'pure' (I can't explain this - if you can you should believe this answer much more).
'sot' with letters rearranged gives 'ost'.
'ost' placed within 'pure' is 'POSTURE'.
Can you help me to learn more?
(Other definitions for posture that I've seen before include "Bodily stance" , "The way a person stands or sits" , "Stance adopted by Proteus" , "Pose or position" , "Way of bearing one's body" .)