Opening with a saucy turn again (8)
I believe the answer is:
aperture
'opening' is the definition.
(aperture is a kind of opening)
'a saucy turn again' is the wordplay.
'saucy' becomes 'pert' ('pert' can be a synonym of 'saucy').
'turn' becomes 'u' (a 'U-turn' is a kind of turn).
'again' becomes 're'.
'a'+'pert'+'u'+'re'='APERTURE'
'with' acts as a link.
(Other definitions for aperture that I've seen before include "Narrow opening" , "'Hole, opening (8)'" , "Opening, gap" , "Crack" , "Opening (for a photographer?)" .)