Coyest nurses agreed (3)
I believe the answer is:
yes
'agreed' is the definition.
('agreed' can mean 'yes')
'coyest nurses' is the wordplay.
'nurses' indicates a hidden word (nurse can mean holding closely).
'YES' can be found hidden inside 'coyest'.
(Other definitions for yes that I've seen before include "Of course" , "Yea" , "Affirmative answer" , "Aye" , "Agreed" .)