Coward, say, awfully wary, in dire straits (10)
I believe the answer is:
playwright
'coward say' is the definition.
(I know that Noel Coward is a playwright)
'awfully wary in dire straits' is the wordplay.
'awfully' indicates anagramming the letters.
'in' indicates putting letters inside.
'dire straits' becomes 'plight' (dire straits means trouble or plight).
'wary' anagrammed gives 'aywr'.
'aywr' put inside 'plight' is 'PLAYWRIGHT'.
(Other definitions for playwright that I've seen before include "Stoppard or Pinter, for example" , "Author of dramas" , "Shakespeare perhaps" , "Coward, possibly" , "Dramatist" .)