Pub much obliged for an order (7)
I believe the answer is:
taproom
'pub' is the definition.
(thesaurus)
'much obliged for an order' is the wordplay.
'much obliged' becomes 'ta' (both are ways of saying thank you).
'for' becomes 'pro' (as in being 'pro' something).
'an order' becomes 'om' (Order of Merit).
'ta'+'pro'+'om'='TAPROOM'
(Other definitions for taproom that I've seen before include "part of pub" , "Source of beer" , "Type of bar" , "Hotel bar" , "liquor shop" .)