Doctor holding delicate fabric up still (6)
I believe the answer is:
becalm
'still' is the definition.
(thesaurus)
'doctor holding delicate fabric up' is the wordplay.
'doctor' becomes 'mb' (Bachelor of Medicine, Medicinae Baccalaureus).
'holding' indicates putting letters inside.
'delicate fabric' becomes 'lace' (I've seen this before).
'up' shows that the letters should be reversed in order (in down clue: letters go upwards).
'mb' going around 'lace' is 'mlaceb'.
'mlaceb' backwards is 'BECALM'.
(Other definitions for becalm that I've seen before include "Leave (sailing ship) without wind" , "Leave (sailing ship) unable to move" , "Make quiet or still - sounds like an order" , "Make still (from lack of wind)" , "don't get the wind up" .)