One of Wingate's men's language in court (7)
I believe the answer is:
chindit
'one of wingate's men's' is the definition.
(the Chindits were commanded by Orde Wingate in WW2)
'language in court' is the wordplay.
'language' becomes 'hindi' (Hindi is an example).
'in' means one lot of letters goes inside another.
'court' becomes 'ct' (abbreviation used in road names).
'hindi' placed inside 'ct' is 'CHINDIT'.
(Other definitions for chindit that I've seen before include "WW2 allied commando in Burma" , "Burmese fighter" , "WW2 soldier" , "Old fighter in Burma" .)