Spout, round and long (5)
I believe the answer is:
opine
'spout' is the definition.
(I've seen this in another clue)
'round and long' is the wordplay.
'round' becomes 'o' (round can mean a round object).
'and' is a charade indicator (letters next to each other).
'long' becomes 'pine' (to pine for someone is to long for them).
'o'+'pine'='OPINE'
(Other definitions for opine that I've seen before include "Give one's view" , "Think - express a view" , "State one's held view" , "Express or hold view" , "Hold forth" .)