Light breeze round the West (6)
I believe the answer is:
window
'light' is the definition.
(light can mean a window or opening)
'breeze round the west' is the wordplay.
'breeze' becomes 'wind' (a breeze is a slight wind).
'round' becomes 'o' (o is a circular letter).
'the west' becomes 'W' (abbreviation).
'wind'+'o'+'w'='WINDOW'
(Other definitions for window that I've seen before include "See 8" , "Opening in a wall" , "Clear panel in envelope" , "time still available" , "Shop display area" .)