Time old working lawyer employed in city (7)
I believe the answer is:
noonday
'time' is the definition.
(noonday is a kind of time)
'old working lawyer employed in city' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'working' becomes 'on'.
'lawyer' becomes 'da' (D.A. is an example).
'employed in' means one lot of letters goes inside another.
'city' becomes 'ny' (I've seen this in other clues**).
'o'+'on'+'da'='oonda'
'oonda' put inside 'ny' is 'NOONDAY'.
(Other definitions for noonday that I've seen before include "12 o'clock" , "Twelve a.m." , "Meridional" , "time of greatest prosperity" , "Midday, 12p.m." .)