Extract from nasty letter, in a way (5)
I believe the answer is:
style
'a way' is the definition.
('style' can be a synonym of 'way')
'extract from nasty letter in' is the wordplay.
'extract from' indicates the answer is hidden within the clue (I've seen this in other clues).
'STYLE' is hidden in the letters of 'nasty letter in'.
(Other definitions for style that I've seen before include "Elan" , "Distinctive manner" , "Fashion or way of doing things" , "Fashion or design" , "Elegance, sophistication" .)