Flow from spout holding single drink (9)
I believe the answer is:
originate
'flow' is the definition.
(thesaurus)
'spout holding single drink' is the wordplay.
'spout' becomes 'orate' (both can mean to speak or proclaim).
'holding' means one lot of letters goes inside another.
'single' becomes 'I' (one).
'drink' becomes 'gin' (gin is an alcoholic drink).
'i'+'gin'='igin'
'orate' placed around 'igin' is 'ORIGINATE'.
'from' is the link.
(Other definitions for originate that I've seen before include "Create; begin" , "Create, initiate" , "Come into existence" , "Launch" , "Bring into existence" .)