Sightseer, one in French city close to coast (7)
I believe the answer is:
tourist
'sightseer' is the definition.
(thesaurus)
'one in french city close to coast' is the wordplay.
'one' becomes 'i' (Roman numeral).
'in' means one lot of letters goes inside another.
'french city' becomes 'tours' (I've seen this before**).
'close to' suggests the final letters (the close/ending of).
The last letter of 'coast' is 't'.
'i' placed inside 'tours' is 'touris'.
'touris'+'t'='TOURIST'
(Other definitions for tourist that I've seen before include "Visiting sightseer" , "Sightseeing traveller" , "someone on holiday" , "Tripper, sightseer" , "Traveller for pleasure" .)