Architectural feature one associated with clubs in city (7)
I believe the answer is:
portico
'architectural feature' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'one associated with clubs in city' is the wordplay.
'one' becomes 'i' (Roman numeral).
'associated with' says to put letters next to each other.
'clubs' becomes 'c' (abbreviation used in card games such as bridge).
'in' means one lot of letters goes inside another.
'city' becomes 'porto' (I have seen 'Portuguese city ' mean 'porto' so perhaps 'city' could also mean 'porto').
'i'+'c'='ic'
'ic' going inside 'porto' is 'PORTICO'.
Can you help me to learn more?
(Other definitions for portico that I've seen before include "series of columns" , "covered area" , "Porch-like structure with columns" , "Covered porch with supporting columns" , "Posh covered entrance to building" .)