Old court letter exposed Group of Eight (7)
I believe the answer is:
octette
'group of eight' is the definition.
(I've seen this before)
'old court letter exposed' is the wordplay.
'old' becomes 'o' (abbreviation).
'court' becomes 'ct' (abbreviation used in road names).
'exposed' means to look at the middle letters (the inside of the word is exposed).
The middle letters of 'letter' are 'ette'.
'o'+'ct'+'ette'='OCTETTE'
(Other definitions for octette that I've seen before include "Eight musicians" , "Noted work" , "Group of eight" .)