Star starts to order lobster in the city (7)
I believe the answer is:
polaris
'star' is the definition.
(star within the constellation Ursa Minor)
'starts to order lobster in the city' is the wordplay.
'starts to' indicates taking the first letters.
'in the' indicates putting letters inside.
'city' becomes 'paris' (Paris is an example).
The first letters of 'order lobster' is 'ol'.
'ol' going within 'paris' is 'POLARIS'.
(Other definitions for polaris that I've seen before include "weapon sailors unleash" , "North Star - missile" , "Star near the N pole of the heavens" , "one belonging in the heavens" , "star (non-movie)" .)