Raise section of steel bonnet from below (7)
I believe the answer is:
ennoble
'raise' is the definition.
(I know that ennoble is a more specific form of the action raise)
'section of steel bonnet from below' is the wordplay.
'section of' says the answer is hidden in the clue.
'from below' shows that the letters should be reversed in order (in a down clue, letters go up).
'elbonne' is hidden within 'steel bonnet'.
'elbonne' reversed gives 'ENNOBLE'.
(Other definitions for ennoble that I've seen before include "Exalt" , "Elevate to knighthood" , "Raise to greater dignity" , "Kick upstairs" , "Aggrandise" .)