River swallows up golf drive (4)
I believe the answer is:
urge
'drive' is the definition.
(thesaurus)
'river swallows up golf' is the wordplay.
'river' becomes 'ure' (I have seen 'River of Wensleydale ' mean 'ure' so perhaps 'river' could also mean 'ure').
'swallows up' means one lot of letters goes inside another.
'golf' becomes 'g' (phonetic alphabet: alpha, bravo, charlie etc.).
'ure' enclosing 'g' is 'URGE'.
(Other definitions for urge that I've seen before include "Constrain" , "Advocate" , "Impel - impulse" , "Capital of Colombia" , "Press (persistently)" .)