Brother describes leading restaurant (6)
I believe the answer is:
bistro
'restaurant' is the definition.
(I know that bistro is a type of restaurant)
'brother describes leading' is the wordplay.
'brother' becomes 'bro' (short for brother).
'describes' is an insertion indicator (describe can mean to form the outline of).
'leading' becomes 'ist' (I am not sure about this - if you are sure you should believe this answer much more).
'bro' going around 'ist' is 'BISTRO'.
Can you help me to learn more?
(Other definitions for bistro that I've seen before include "Little restaurant" , "Cafe bar" , "Cheap restaurant" , "Intimate eatery" , "family concern perhaps" .)