Cringe frightfully, suppressing cry of pain, doing this? (8)
I believe the answer is:
cowering
'doing this?' is the definition.
The definition suggests a singular noun but the answer is not.
'cringe frightfully suppressing cry of pain' is the wordplay.
'frightfully' indicates anagramming the letters.
'suppressing' is an insertion indicator.
'cry of pain' becomes 'ow' (I've seen this in other clues).
'cringe' with letters rearranged gives 'cering'.
'cering' enclosing 'ow' is 'COWERING'.
(Other definitions for cowering that I've seen before include "Crouching down in fear" , "Drawing back" , "Cringing in fear" .)