Travelling detectives about to return, pursuing French name (7)
I believe the answer is:
nomadic
'travelling' is the definition.
(I've seen this before)
'detectives about to return pursuing french name' is the wordplay.
'detectives' becomes 'CID' (abbreviation for Criminal Investigation Department).
'about' becomes 'a' (abbreviation in Chambers).
'to return' is a reversal indicator.
'pursuing' is a charade indicator (letters next to each other).
'french name' becomes 'nom' ('name' in French).
'cid'+'a'='cida'
'cida' backwards is 'adic'.
'adic' after 'nom' is 'NOMADIC'.
(Other definitions for nomadic that I've seen before include "Migratory" , "Given to wandering like travellers or Bedouins" , "Homeless - wandering" , "migrant" , "Of no fixed abode" .)