Woman left before break of day (4)
I believe the answer is:
lady
'woman' is the definition.
(I know that Lady is a type of woman)
'left before break of day' is the wordplay.
'left' becomes 'l' (common abbreviation).
'before' says to put letters next to each other.
'break of' is an anagram indicator (I've seen 'broken' mean this).
'day' is an anagram of 'ady'.
'l'+'ady'='LADY'
(Other definitions for lady that I've seen before include "Noble" , "Lord's wife - peeress's title" , "Lord's partner" , "See 7" , "Title for a knight's wife" .)