Highly strung nurse goes out about five to ring (7)
I believe the answer is:
nervous
'highly strung' is the definition.
(I've seen this before)
'nurse goes out about five to ring' is the wordplay.
'goes out' indicates anagramming the letters.
'about' is an insertion indicator.
'five' becomes 'V' (Roman numeral).
'to ring' becomes 'o' (letter resembling a ring).
'nurse' is an anagram of 'nerus'.
'v'+'o'='vo'
'nerus' placed around 'vo' is 'NERVOUS'.
(Other definitions for nervous that I've seen before include "full of trepidation" , "far from cool?" , "Jumpy" , "'Apprehensive, uneasy (7)'" , "Fidgety" .)