Parent adrift approaching river entrance (9)
I believe the answer is:
enrapture
'entrance' is the definition.
(I've seen this before)
'parent adrift approaching river' is the wordplay.
'adrift' indicates anagramming the letters.
'approaching' is a charade indicator (letters next to each other).
'river' becomes 'ure' (river in Yorkshire).
'parent' anagrammed gives 'enrapt'.
'enrapt'+'ure'='ENRAPTURE'
(Other definitions for enrapture that I've seen before include "entrance" , "Give intense pleasure to" , "Transport" , "Bewitch" , "Ape Turner (anag.)" .)