Approach clear river (8)
I believe the answer is:
overture
'approach' is the definition.
(I know that approach can be written as overture)
'clear river' is the wordplay.
'clear' becomes 'overt' (both can mean apparent or obvious).
'river' becomes 'ure' (river in Yorkshire).
'overt'+'ure'='OVERTURE'
(Other definitions for overture that I've seen before include "Orchestral introduction to an opera" , "Tender - piece of music" , "musical composition" , "Orchestral music at the beginning of an opera" , "Introductory section" .)